1 '\" te
   2 .\" Copyright 1989 AT&T
   3 .\" Copyright (c) 2006, Sun Microsystems, Inc. All Rights Reserved.
   4 .\" Copyright 2018, Joyent, Inc.
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   7 .\" When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE.  If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
   8 .TH PROC 4 "August 22, 2018"
   9 .SH NAME
  10 proc \- /proc, the process file system
  11 .SH DESCRIPTION
  12 .LP
  13 \fB/proc\fR is a file system that provides access to the state of each process
  14 and light-weight process (lwp) in the system. The name of each entry in the
  15 \fB/proc\fR directory is a decimal number corresponding to a process-ID. These
  16 entries are themselves subdirectories. Access to process state is provided by
  17 additional files contained within each subdirectory; the hierarchy is described
  18 more completely below. In this document, ``\fB/proc\fR file'' refers to a
  19 non-directory file within the hierarchy rooted at \fB/proc\fR. The owner of
  20 each \fB/proc\fR file and subdirectory is determined by the user-ID of the
  21 process.
  22 .sp
  23 .LP
  24 \fB/proc\fR can be mounted on any mount point, in addition to the standard
  25 \fB/proc\fR mount point, and can be mounted several places at once. Such
  26 additional mounts are allowed in order to facilitate the confinement of
  27 processes to subtrees of the file system via \fBchroot\fR(1M) and yet allow
  28 such processes access to commands like \fBps\fR(1).
  29 .sp
  30 .LP
  31 Standard system calls are used to access \fB/proc\fR files: \fBopen\fR(2),
  32 \fBclose\fR(2), \fBread\fR(2), and \fBwrite\fR(2) (including \fBreadv\fR(2),
  33 \fBwritev\fR(2), \fBpread\fR(2), and \fBpwrite\fR(2)). Most files describe
  34 process state and can only be opened for reading. \fBctl\fR and \fBlwpctl\fR
  35 (control) files permit manipulation of process state and can only be opened for
  36 writing. \fBas\fR (address space) files contain the image of the running
  37 process and can be opened for both reading and writing. An open for writing
  38 allows process control; a read-only open allows inspection but not control. In
  39 this document, we refer to the process as open for reading or writing if any of
  40 its associated \fB/proc\fR files is open for reading or writing.
  41 .sp
  42 .LP
  43 In general, more than one process can open the same \fB/proc\fR file at the
  44 same time. \fIExclusive\fR \fIopen\fR is an advisory mechanism provided to
  45 allow controlling processes to avoid collisions with each other. A process can
  46 obtain exclusive control of a target process, with respect to other cooperating
  47 processes, if it successfully opens any \fB/proc\fR file in the target process
  48 for writing (the \fBas\fR or \fBctl\fR files, or the \fBlwpctl\fR file of any
  49 lwp) while specifying \fBO_EXCL\fR in the \fBopen\fR(2). Such an open will fail
  50 if the target process is already open for writing (that is, if an \fBas\fR,
  51 \fBctl\fR, or \fBlwpctl\fR file is already open for writing). There can be any
  52 number of concurrent read-only opens; \fBO_EXCL\fR is ignored on opens for
  53 reading. It is recommended that the first open for writing by a controlling
  54 process use the \fBO_EXCL\fR flag; multiple controlling processes usually
  55 result in chaos.
  56 .sp
  57 .LP
  58 If a process opens one of its own \fB/proc\fR files for writing, the open
  59 succeeds regardless of \fBO_EXCL\fR and regardless of whether some other
  60 process has the process open for writing. Self-opens do not count when another
  61 process attempts an exclusive open. (A process cannot exclude a debugger by
  62 opening itself for writing and the application of a debugger cannot prevent a
  63 process from opening itself.) All self-opens for writing are forced to be
  64 close-on-exec (see the \fBF_SETFD\fR operation of \fBfcntl\fR(2)).
  65 .sp
  66 .LP
  67 Data may be transferred from or to any locations in the address space of the
  68 traced process by applying \fBlseek\fR(2) to position the \fBas\fR file at the
  69 virtual address of interest followed by \fBread\fR(2) or \fBwrite\fR(2) (or by
  70 using \fBpread\fR(2) or \fBpwrite\fR(2) for the combined operation). The
  71 address-map files \fB/proc/\fR\fIpid\fR\fB/map\fR and
  72 \fB/proc/\fR\fIpid\fR\fB/xmap\fR can be read to determine the accessible areas
  73 (mappings) of the address space. \fBI/O\fR transfers may span contiguous
  74 mappings. An \fBI/O\fR request extending into an unmapped area is truncated at
  75 the boundary. A write request beginning at an unmapped virtual address fails
  76 with \fBEIO\fR; a read request beginning at an unmapped virtual address returns
  77 zero (an end-of-file indication).
  78 .sp
  79 .LP
  80 Information and control operations are provided through additional files.
  81 \fB<procfs.h>\fR contains definitions of data structures and message formats
  82 used with these files. Some of these definitions involve the use of sets of
  83 flags. The set types \fBsigset_t\fR, \fBfltset_t\fR, and \fBsysset_t\fR
  84 correspond, respectively, to signal, fault, and system call enumerations
  85 defined in \fB<sys/signal.h>\fR, \fB<sys/fault.h>\fR, and
  86 \fB<sys/syscall.h>\fR\&. Each set type is large enough to hold flags for its
  87 own enumeration. Although they are of different sizes, they have a common
  88 structure and can be manipulated by these macros:
  89 .sp
  90 .in +2
  91 .nf
  92 prfillset(&set);             /* turn on all flags in set */
  93 premptyset(&set);            /* turn off all flags in set */
  94 praddset(&set, flag);        /* turn on the specified flag */
  95 prdelset(&set, flag);        /* turn off the specified flag */
  96 r = prismember(&set, flag);  /* != 0 iff flag is turned on */
  97 .fi
  98 .in -2
  99 
 100 .sp
 101 .LP
 102 One of \fBprfillset()\fR or \fBpremptyset()\fR must be used to initialize
 103 \fBset\fR before it is used in any other operation. \fBflag\fR must be a member
 104 of the enumeration corresponding to \fBset\fR.
 105 .sp
 106 .LP
 107 Every process contains at least one \fIlight-weight process\fR, or \fIlwp\fR.
 108 Each lwp represents a flow of execution that is independently scheduled by the
 109 operating system. All lwps in a process share its address space as well as many
 110 other attributes. Through the use of \fBlwpctl\fR and \fBctl\fR files as
 111 described below, it is possible to affect individual lwps in a process or to
 112 affect all of them at once, depending on the operation.
 113 .sp
 114 .LP
 115 When the process has more than one lwp, a representative lwp is chosen by the
 116 system for certain process status files and control operations. The
 117 representative lwp is a stopped lwp only if all of the process's lwps are
 118 stopped; is stopped on an event of interest only if all of the lwps are so
 119 stopped (excluding \fBPR_SUSPENDED\fR lwps); is in a \fBPR_REQUESTED\fR stop
 120 only if there are no other events of interest to be found; or, failing
 121 everything else, is in a \fBPR_SUSPENDED\fR stop (implying that the process is
 122 deadlocked). See the description of the \fBstatus\fR file for definitions of
 123 stopped states. See the \fBPCSTOP\fR control operation for the definition of
 124 ``event of interest''.
 125 .sp
 126 .LP
 127 The representative lwp remains fixed (it will be chosen again on the next
 128 operation) as long as all of the lwps are stopped on events of interest or are
 129 in a \fBPR_SUSPENDED\fR stop and the \fBPCRUN\fR control operation is not
 130 applied to any of them.
 131 .sp
 132 .LP
 133 When applied to the process control file, every \fB/proc\fR control operation
 134 that must act on an lwp uses the same algorithm to choose which lwp to act
 135 upon. Together with synchronous stopping (see \fBPCSET\fR), this enables a
 136 debugger to control a multiple-lwp process using only the process-level status
 137 and control files if it so chooses. More fine-grained control can be achieved
 138 using the lwp-specific files.
 139 .sp
 140 .LP
 141 The system supports two process data models, the traditional 32-bit data model
 142 in which ints, longs and pointers are all 32 bits wide (the ILP32 data model),
 143 and on some platforms the 64-bit data model in which longs and pointers, but
 144 not ints, are 64 bits in width (the LP64 data model). In the LP64 data model
 145 some system data types, notably \fBsize_t\fR, \fBoff_t\fR, \fBtime_t\fR and
 146 \fBdev_t\fR, grow from 32 bits to 64 bits as well.
 147 .sp
 148 .LP
 149 The \fB/proc\fR interfaces described here are available to both 32-bit and
 150 64-bit controlling processes. However, many operations attempted by a 32-bit
 151 controlling process on a 64-bit target process will fail with \fBEOVERFLOW\fR
 152 because the address space range of a 32-bit process cannot encompass a 64-bit
 153 process or because the data in some 64-bit system data type cannot be
 154 compressed to fit into the corresponding 32-bit type without loss of
 155 information. Operations that fail in this circumstance include reading and
 156 writing the address space, reading the address-map files, and setting the
 157 target process's registers. There is no restriction on operations applied by a
 158 64-bit process to either a 32-bit or a 64-bit target processes.
 159 .sp
 160 .LP
 161 The format of the contents of any \fB/proc\fR file depends on the data model of
 162 the observer (the controlling process), not on the data model of the target
 163 process. A 64-bit debugger does not have to translate the information it reads
 164 from a \fB/proc\fR file for a 32-bit process from 32-bit format to 64-bit
 165 format. However, it usually has to be aware of the data model of the target
 166 process. The \fBpr_dmodel\fR field of the \fBstatus\fR files indicates the
 167 target process's data model.
 168 .sp
 169 .LP
 170 To help deal with system data structures that are read from 32-bit processes, a
 171 64-bit controlling program can be compiled with the C preprocessor symbol
 172 \fB_SYSCALL32\fR defined before system header files are included. This makes
 173 explicit 32-bit fixed-width data structures (like \fBcstruct stat32\fR) visible
 174 to the 64-bit program. See \fBtypes32.h\fR(3HEAD).
 175 .SH DIRECTORY STRUCTURE
 176 .LP
 177 At the top level, the directory \fB/proc\fR contains entries each of which
 178 names an existing process in the system. These entries are themselves
 179 directories. Except where otherwise noted, the files described below can be
 180 opened for reading only. In addition, if a process becomes a \fIzombie\fR (one
 181 that has exited but whose parent has not yet performed a \fBwait\fR(3C) upon
 182 it), most of its associated \fB/proc\fR files disappear from the hierarchy;
 183 subsequent attempts to open them, or to read or write files opened before the
 184 process exited, will elicit the error \fBENOENT\fR.
 185 .sp
 186 .LP
 187 Although process state and consequently the contents of \fB/proc\fR files can
 188 change from instant to instant, a single \fBread\fR(2) of a \fB/proc\fR file is
 189 guaranteed to return a sane representation of state; that is, the read will be
 190 atomic with respect to the state of the process. No such guarantee applies to
 191 successive reads applied to a \fB/proc\fR file for a running process. In
 192 addition, atomicity is not guaranteed for \fBI/O\fR applied to the \fBas\fR
 193 (address-space) file for a running process or for a process whose address space
 194 contains memory shared by another running process.
 195 .sp
 196 .LP
 197 A number of structure definitions are used to describe the files. These
 198 structures may grow by the addition of elements at the end in future releases
 199 of the system and it is not legitimate for a program to assume that they will
 200 not.
 201 .SH STRUCTURE OF \fB/proc/\fR\fIpid\fR
 202 .LP
 203 A given directory \fB/proc/\fR\fIpid\fR contains the following entries. A
 204 process can use the invisible alias \fB/proc/self\fR if it wishes to open one
 205 of its own \fB/proc\fR files (invisible in the sense that the name ``self''
 206 does not appear in a directory listing of \fB/proc\fR obtained from
 207 \fBls\fR(1), \fBgetdents\fR(2), or \fBreaddir\fR(3C)).
 208 .SS "contracts"
 209 .LP
 210 A directory containing references to the contracts held by the process. Each
 211 entry is a symlink to the contract's directory under \fB/system/contract\fR.
 212 See \fBcontract\fR(4).
 213 .SS "as"
 214 .LP
 215 Contains the address-space image of the process; it can be opened for both
 216 reading and writing. \fBlseek\fR(2) is used to position the file at the virtual
 217 address of interest and then the address space can be examined or changed
 218 through \fBread\fR(2) or \fBwrite\fR(2) (or by using \fBpread\fR(2) or
 219 \fBpwrite\fR(2) for the combined operation).
 220 .SS "ctl"
 221 .LP
 222 A write-only file to which structured messages are written directing the system
 223 to change some aspect of the process's state or control its behavior in some
 224 way. The seek offset is not relevant when writing to this file. Individual lwps
 225 also have associated \fBlwpctl\fR files in the lwp subdirectories. A control
 226 message may be written either to the process's \fBctl\fR file or to a specific
 227 \fBlwpctl\fR file with operation-specific effects. The effect of a control
 228 message is immediately reflected in the state of the process visible through
 229 appropriate status and information files. The types of control messages are
 230 described in detail later. See \fBCONTROL MESSAGES\fR.
 231 .SS "status"
 232 .LP
 233 Contains state information about the process and the representative lwp. The
 234 file contains a \fBpstatus\fR structure which contains an embedded
 235 \fBlwpstatus\fR structure for the representative lwp, as follows:
 236 .sp
 237 .in +2
 238 .nf
 239 typedef struct pstatus {
 240      int pr_flags;            /* flags (see below) */
 241      int pr_nlwp;             /* number of active lwps in the process */
 242      int pr_nzomb;            /* number of zombie lwps in the process */
 243      pid_tpr_pid;             /* process id */
 244      pid_tpr_ppid;            /* parent process id */
 245      pid_tpr_pgid;            /* process group id */
 246      pid_tpr_sid;             /* session id */
 247      id_t pr_aslwpid;         /* obsolete */
 248      id_t pr_agentid;         /* lwp-id of the agent lwp, if any */
 249      sigset_t pr_sigpend;     /* set of process pending signals */
 250      uintptr_t pr_brkbase;    /* virtual address of the process heap */
 251      size_t pr_brksize;       /* size of the process heap, in bytes */
 252      uintptr_t pr_stkbase;    /* virtual address of the process stack */
 253      size_tpr_stksize;        /* size of the process stack, in bytes */
 254      timestruc_t pr_utime;    /* process user cpu time */
 255      timestruc_t pr_stime;    /* process system cpu time */
 256      timestruc_t pr_cutime;   /* sum of children's user times */
 257      timestruc_t pr_cstime;   /* sum of children's system times */
 258      sigset_t pr_sigtrace;    /* set of traced signals */
 259      fltset_t pr_flttrace;    /* set of traced faults */
 260      sysset_t pr_sysentry;    /* set of system calls traced on entry */
 261      sysset_t pr_sysexit;     /* set of system calls traced on exit */
 262      char pr_dmodel;          /* data model of the process */
 263      taskid_t pr_taskid;      /* task id */
 264      projid_t pr_projid;      /* project id */
 265      zoneid_t pr_zoneid;      /* zone id */
 266      lwpstatus_t pr_lwp;      /* status of the representative lwp */
 267 } pstatus_t;
 268 .fi
 269 .in -2
 270 
 271 .sp
 272 .LP
 273 \fBpr_flags\fR is a bit-mask holding the following process flags. For
 274 convenience, it also contains the lwp flags for the representative lwp,
 275 described later.
 276 .sp
 277 .ne 2
 278 .na
 279 \fB\fBPR_ISSYS\fR\fR
 280 .ad
 281 .RS 13n
 282 process is a system process (see \fBPCSTOP\fR).
 283 .RE
 284 
 285 .sp
 286 .ne 2
 287 .na
 288 \fB\fBPR_VFORKP\fR\fR
 289 .ad
 290 .RS 13n
 291 process is the parent of a vforked child (see \fBPCWATCH\fR).
 292 .RE
 293 
 294 .sp
 295 .ne 2
 296 .na
 297 \fB\fBPR_FORK\fR\fR
 298 .ad
 299 .RS 13n
 300 process has its inherit-on-fork mode set (see \fBPCSET\fR).
 301 .RE
 302 
 303 .sp
 304 .ne 2
 305 .na
 306 \fB\fBPR_RLC\fR\fR
 307 .ad
 308 .RS 13n
 309 process has its run-on-last-close mode set (see \fBPCSET\fR).
 310 .RE
 311 
 312 .sp
 313 .ne 2
 314 .na
 315 \fB\fBPR_KLC\fR\fR
 316 .ad
 317 .RS 13n
 318 process has its kill-on-last-close mode set (see \fBPCSET\fR).
 319 .RE
 320 
 321 .sp
 322 .ne 2
 323 .na
 324 \fB\fBPR_ASYNC\fR\fR
 325 .ad
 326 .RS 13n
 327 process has its asynchronous-stop mode set (see \fBPCSET\fR).
 328 .RE
 329 
 330 .sp
 331 .ne 2
 332 .na
 333 \fB\fBPR_MSACCT\fR\fR
 334 .ad
 335 .RS 13n
 336 Set by default in all processes to indicate that microstate accounting is
 337 enabled. However, this flag has been deprecated and no longer has any effect.
 338 Microstate accounting may not be disabled; however, it is still possible to
 339 toggle the flag.
 340 .RE
 341 
 342 .sp
 343 .ne 2
 344 .na
 345 \fB\fBPR_MSFORK\fR\fR
 346 .ad
 347 .RS 13n
 348 Set by default in all processes to indicate that microstate accounting will be
 349 enabled for processes that this parent forks(). However, this flag has been
 350 deprecated and no longer has any effect. It is possible to toggle this flag;
 351 however, it is not possible to disable microstate accounting.
 352 .RE
 353 
 354 .sp
 355 .ne 2
 356 .na
 357 \fB\fBPR_BPTADJ\fR\fR
 358 .ad
 359 .RS 13n
 360 process has its breakpoint adjustment mode set (see \fBPCSET\fR).
 361 .RE
 362 
 363 .sp
 364 .ne 2
 365 .na
 366 \fB\fBPR_PTRACE\fR\fR
 367 .ad
 368 .RS 13n
 369 process has its ptrace-compatibility mode set (see \fBPCSET\fR).
 370 .RE
 371 
 372 .sp
 373 .LP
 374 \fBpr_nlwp\fR is the total number of active lwps in the process. pr_nzomb is
 375 the total number of zombie lwps in the process. A zombie lwp is a non-detached
 376 lwp that has terminated but has not been reaped with \fBthr_join\fR(3C) or
 377 \fBpthread_join\fR(3C).
 378 .sp
 379 .LP
 380 \fBpr_pid\fR, \fBpr_ppid\fR, \fBpr_pgid\fR, and \fBpr_sid\fR are, respectively,
 381 the process ID, the ID of the process's parent, the process's process group ID,
 382 and the process's session ID.
 383 .sp
 384 .LP
 385 \fBpr_aslwpid\fR is obsolete and is always zero.
 386 .sp
 387 .LP
 388 \fBpr_agentid\fR is the lwp-ID for the \fB/proc\fR agent lwp (see the
 389 \fBPCAGENT\fR control operation). It is zero if there is no agent lwp in the
 390 process.
 391 .sp
 392 .LP
 393 \fBpr_sigpend\fR identifies asynchronous signals pending for the process.
 394 .sp
 395 .LP
 396 \fBpr_brkbase\fR is the virtual address of the process heap and
 397 \fBpr_brksize\fR is its size in bytes. The address formed by the sum of these
 398 values is the process \fBbreak\fR (see \fBbrk\fR(2)). \fBpr_stkbase\fR and
 399 \fBpr_stksize\fR are, respectively, the virtual address of the process stack
 400 and its size in bytes. (Each lwp runs on a separate stack; the distinguishing
 401 characteristic of the process stack is that the operating system will grow it
 402 when necessary.)
 403 .sp
 404 .LP
 405 \fBpr_utime\fR, \fBpr_stime\fR, \fBpr_cutime\fR, and \fBpr_cstime\fR are,
 406 respectively, the user \fBCPU\fR and system \fBCPU\fR time consumed by the
 407 process, and the cumulative user \fBCPU\fR and system \fBCPU\fR time consumed
 408 by the process's children, in seconds and nanoseconds.
 409 .sp
 410 .LP
 411 \fBpr_sigtrace\fR and \fBpr_flttrace\fR contain, respectively, the set of
 412 signals and the set of hardware faults that are being traced (see
 413 \fBPCSTRACE\fR and \fBPCSFAULT\fR).
 414 .sp
 415 .LP
 416 \fBpr_sysentry\fR and \fBpr_sysexit\fR contain, respectively, the sets of
 417 system calls being traced on entry and exit (see \fBPCSENTRY\fR and
 418 \fBPCSEXIT\fR).
 419 .sp
 420 .LP
 421 \fBpr_dmodel\fR indicates the data model of the process. Possible values are:
 422 .sp
 423 .ne 2
 424 .na
 425 \fB\fBPR_MODEL_ILP32\fR\fR
 426 .ad
 427 .RS 19n
 428 process data model is ILP32.
 429 .RE
 430 
 431 .sp
 432 .ne 2
 433 .na
 434 \fB\fBPR_MODEL_LP64\fR\fR
 435 .ad
 436 .RS 19n
 437 process data model is LP64.
 438 .RE
 439 
 440 .sp
 441 .ne 2
 442 .na
 443 \fB\fBPR_MODEL_NATIVE\fR\fR
 444 .ad
 445 .RS 19n
 446 process data model is native.
 447 .RE
 448 
 449 .sp
 450 .LP
 451 The \fBpr_taskid\fR, \fBpr_projid\fR, and \fBpr_zoneid\fR fields contain
 452 respectively, the numeric \fBID\fRs of the task, project, and zone in which the
 453 process was running.
 454 .sp
 455 .LP
 456 The constant \fBPR_MODEL_NATIVE\fR reflects the data model of the controlling
 457 process, \fIthat is\fR, its value is \fBPR_MODEL_ILP32\fR or
 458 \fBPR_MODEL_LP64\fR according to whether the controlling process has been
 459 compiled as a 32-bit program or a 64-bit program, respectively.
 460 .sp
 461 .LP
 462 \fBpr_lwp\fR contains the status information for the representative lwp:
 463 .sp
 464 .in +2
 465 .nf
 466 typedef struct lwpstatus {
 467   int pr_flags;              /* flags (see below) */
 468   id_t pr_lwpid;             /* specific lwp identifier */
 469   short pr_why;              /* reason for lwp stop, if stopped */
 470   short pr_what;             /* more detailed reason */
 471   short pr_cursig;           /* current signal, if any */
 472   siginfo_t pr_info;         /* info associated with signal or fault */
 473   sigset_t pr_lwppend;       /* set of signals pending to the lwp */
 474   sigset_t pr_lwphold;       /* set of signals blocked by the lwp */
 475   struct sigaction pr_action;/* signal action for current signal */
 476   stack_t pr_altstack;       /* alternate signal stack info */
 477   uintptr_t pr_oldcontext;   /* address of previous ucontext */
 478   short pr_syscall;          /* system call number (if in syscall) */
 479   short pr_nsysarg;          /* number of arguments to this syscall */
 480   int pr_errno;              /* errno for failed syscall */
 481   long pr_sysarg[PRSYSARGS]; /* arguments to this syscall */
 482   long pr_rval1;             /* primary syscall return value */
 483   long pr_rval2;             /* second syscall return value, if any */
 484   char pr_clname[PRCLSZ];    /* scheduling class name */
 485   timestruc_t pr_tstamp;     /* real-time time stamp of stop */
 486   timestruc_t pr_utime;      /* lwp user cpu time */
 487   timestruc_t pr_stime;      /* lwp system cpu time */
 488   uintptr_t pr_ustack;       /* stack boundary data (stack_t) address */
 489   ulong_t pr_instr;          /* current instruction */
 490   prgregset_t pr_reg;        /* general registers */
 491   prfpregset_t pr_fpreg;     /* floating-point registers */
 492 } lwpstatus_t;
 493 .fi
 494 .in -2
 495 
 496 .sp
 497 .LP
 498 \fBpr_flags\fR is a bit-mask holding the following lwp flags. For convenience,
 499 it also contains the process flags, described previously.
 500 .sp
 501 .ne 2
 502 .na
 503 \fB\fBPR_STOPPED\fR\fR
 504 .ad
 505 .RS 14n
 506 The lwp is stopped.
 507 .RE
 508 
 509 .sp
 510 .ne 2
 511 .na
 512 \fB\fBPR_ISTOP\fR\fR
 513 .ad
 514 .RS 14n
 515 The lwp is stopped on an event of interest (see \fBPCSTOP\fR).
 516 .RE
 517 
 518 .sp
 519 .ne 2
 520 .na
 521 \fB\fBPR_DSTOP\fR\fR
 522 .ad
 523 .RS 14n
 524 The lwp has a stop directive in effect (see \fBPCSTOP\fR).
 525 .RE
 526 
 527 .sp
 528 .ne 2
 529 .na
 530 \fB\fBPR_STEP\fR\fR
 531 .ad
 532 .RS 14n
 533 The lwp has a single-step directive in effect (see \fBPCRUN\fR).
 534 .RE
 535 
 536 .sp
 537 .ne 2
 538 .na
 539 \fB\fBPR_ASLEEP\fR\fR
 540 .ad
 541 .RS 14n
 542 The lwp is in an interruptible sleep within a system call.
 543 .RE
 544 
 545 .sp
 546 .ne 2
 547 .na
 548 \fB\fBPR_PCINVAL\fR\fR
 549 .ad
 550 .RS 14n
 551 The lwp's current instruction (\fBpr_instr\fR) is undefined.
 552 .RE
 553 
 554 .sp
 555 .ne 2
 556 .na
 557 \fB\fBPR_DETACH\fR\fR
 558 .ad
 559 .RS 14n
 560 This is a detached lwp (see \fBpthread_create\fR(3C) and
 561 \fBpthread_join\fR(3C)).
 562 .RE
 563 
 564 .sp
 565 .ne 2
 566 .na
 567 \fB\fBPR_DAEMON\fR\fR
 568 .ad
 569 .RS 14n
 570 This is a daemon lwp (see \fBpthread_create\fR(3C)).
 571 .RE
 572 
 573 .sp
 574 .ne 2
 575 .na
 576 \fB\fBPR_ASLWP\fR\fR
 577 .ad
 578 .RS 14n
 579 This flag is obsolete and is never set.
 580 .RE
 581 
 582 .sp
 583 .ne 2
 584 .na
 585 \fB\fBPR_AGENT\fR\fR
 586 .ad
 587 .RS 14n
 588 This is the \fB/proc\fR agent lwp for the process.
 589 .RE
 590 
 591 .sp
 592 .LP
 593 \fBpr_lwpid\fR names the specific lwp.
 594 .sp
 595 .LP
 596 \fBpr_why\fR and \fBpr_what\fR together describe, for a stopped lwp, the reason
 597 for the stop. Possible values of \fBpr_why\fR and the associated \fBpr_what\fR
 598 are:
 599 .sp
 600 .ne 2
 601 .na
 602 \fB\fBPR_REQUESTED\fR\fR
 603 .ad
 604 .RS 17n
 605 indicates that the stop occurred in response to a stop directive, normally
 606 because \fBPCSTOP\fR was applied or because another lwp stopped on an event of
 607 interest and the asynchronous-stop flag (see \fBPCSET\fR) was not set for the
 608 process. \fBpr_what\fR is unused in this case.
 609 .RE
 610 
 611 .sp
 612 .ne 2
 613 .na
 614 \fB\fBPR_SIGNALLED\fR\fR
 615 .ad
 616 .RS 17n
 617 indicates that the lwp stopped on receipt of a signal (see \fBPCSTRACE\fR);
 618 \fBpr_what\fR holds the signal number that caused the stop (for a newly-stopped
 619 lwp, the same value is in \fBpr_cursig\fR).
 620 .RE
 621 
 622 .sp
 623 .ne 2
 624 .na
 625 \fB\fBPR_FAULTED\fR\fR
 626 .ad
 627 .RS 17n
 628 indicates that the lwp stopped on incurring a hardware fault (see
 629 \fBPCSFAULT\fR); \fBpr_what\fR holds the fault number that caused the stop.
 630 .RE
 631 
 632 .sp
 633 .ne 2
 634 .na
 635 \fB\fBPR_SYSENTRY\fR\fR
 636 .ad
 637 .br
 638 .na
 639 \fB\fBPR_SYSEXIT\fR\fR
 640 .ad
 641 .RS 17n
 642 indicate a stop on entry to or exit from a system call (see \fBPCSENTRY\fR and
 643 \fBPCSEXIT\fR); \fBpr_what\fR holds the system call number.
 644 .RE
 645 
 646 .sp
 647 .ne 2
 648 .na
 649 \fB\fBPR_JOBCONTROL\fR\fR
 650 .ad
 651 .RS 17n
 652 indicates that the lwp stopped due to the default action of a job control stop
 653 signal (see \fBsigaction\fR(2)); \fBpr_what\fR holds the stopping signal
 654 number.
 655 .RE
 656 
 657 .sp
 658 .ne 2
 659 .na
 660 \fB\fBPR_SUSPENDED\fR\fR
 661 .ad
 662 .RS 17n
 663 indicates that the lwp stopped due to internal synchronization of lwps within
 664 the process. \fBpr_what\fR is unused in this case.
 665 .RE
 666 
 667 .sp
 668 .LP
 669 \fBpr_cursig\fR names the current signal, that is, the next signal to be
 670 delivered to the lwp, if any. \fBpr_info\fR, when the lwp is in a
 671 \fBPR_SIGNALLED\fR or \fBPR_FAULTED\fR stop, contains additional information
 672 pertinent to the particular signal or fault (see \fB<sys/siginfo.h>\fR).
 673 .sp
 674 .LP
 675 \fBpr_lwppend\fR identifies any synchronous or directed signals pending for the
 676 lwp. \fBpr_lwphold\fR identifies those signals whose delivery is being blocked
 677 by the lwp (the signal mask).
 678 .sp
 679 .LP
 680 \fBpr_action\fR contains the signal action information pertaining to the
 681 current signal (see \fBsigaction\fR(2)); it is undefined if \fBpr_cursig\fR is
 682 zero. \fBpr_altstack\fR contains the alternate signal stack information for the
 683 lwp (see \fBsigaltstack\fR(2)).
 684 .sp
 685 .LP
 686 \fBpr_oldcontext\fR, if not zero, contains the address on the lwp stack of a
 687 \fBucontext\fR structure describing the previous user-level context (see
 688 \fBucontext.h\fR(3HEAD)). It is non-zero only if the lwp is executing in the
 689 context of a signal handler.
 690 .sp
 691 .LP
 692 \fBpr_syscall\fR is the number of the system call, if any, being executed by
 693 the lwp; it is non-zero if and only if the lwp is stopped on \fBPR_SYSENTRY\fR
 694 or \fBPR_SYSEXIT\fR, or is asleep within a system call ( \fBPR_ASLEEP\fR is
 695 set). If \fBpr_syscall\fR is non-zero, \fBpr_nsysarg\fR is the number of
 696 arguments to the system call and \fBpr_sysarg\fR contains the actual arguments.
 697 .sp
 698 .LP
 699 \fBpr_rval1\fR, \fBpr_rval2\fR, and \fBpr_errno\fR are defined only if the lwp
 700 is stopped on \fBPR_SYSEXIT\fR or if the \fBPR_VFORKP\fR flag is set. If
 701 \fBpr_errno\fR is zero, \fBpr_rval1\fR and \fBpr_rval2\fR contain the return
 702 values from the system call. Otherwise, \fBpr_errno\fR contains the error
 703 number for the failing system call (see \fB<sys/errno.h>\fR).
 704 .sp
 705 .LP
 706 \fBpr_clname\fR contains the name of the lwp's scheduling class.
 707 .sp
 708 .LP
 709 \fBpr_tstamp\fR, if the lwp is stopped, contains a time stamp marking when the
 710 lwp stopped, in real time seconds and nanoseconds since an arbitrary time in
 711 the past.
 712 .sp
 713 .LP
 714 \fBpr_utime\fR is the amount of user level CPU time used by this LWP.
 715 .sp
 716 .LP
 717 \fBpr_stime\fR is the amount of system level CPU time used by this LWP.
 718 .sp
 719 .LP
 720 \fBpr_ustack\fR is the virtual address of the \fBstack_t\fR that contains the
 721 stack boundaries for this LWP. See \fBgetustack\fR(2) and
 722 \fB_stack_grow\fR(3C).
 723 .sp
 724 .LP
 725 \fBpr_instr\fR contains the machine instruction to which the lwp's program
 726 counter refers. The amount of data retrieved from the process is
 727 machine-dependent. On SPARC based machines, it is a 32-bit word. On x86-based
 728 machines, it is a single byte. In general, the size is that of the machine's
 729 smallest instruction. If \fBPR_PCINVAL\fR is set, \fBpr_instr\fR is undefined;
 730 this occurs whenever the lwp is not stopped or when the program counter refers
 731 to an invalid virtual address.
 732 .sp
 733 .LP
 734 \fBpr_reg\fR is an array holding the contents of a stopped lwp's general
 735 registers.
 736 .sp
 737 .ne 2
 738 .na
 739 \fBSPARC\fR
 740 .ad
 741 .RS 21n
 742 On SPARC-based machines, the predefined constants \fBR_G0\fR ... \fBR_G7\fR,
 743 \fBR_O0\fR ... \fBR_O7\fR, \fBR_L0\fR ... \fBR_L7\fR, \fBR_I0\fR ...
 744 \fBR_I7\fR, \fBR_PC\fR, \fBR_nPC\fR, and \fBR_Y\fR can be used as indices to
 745 refer to the corresponding registers; previous register windows can be read
 746 from their overflow locations on the stack (however, see the \fBgwindows\fR
 747 file in the \fB/proc/\fR\fIpid\fR\fB/lwp/\fR\fIlwpid\fR subdirectory).
 748 .RE
 749 
 750 .sp
 751 .ne 2
 752 .na
 753 \fBSPARC V8 (32-bit)\fR
 754 .ad
 755 .RS 21n
 756 For SPARC V8 (32-bit) controlling processes, the predefined constants
 757 \fBR_PSR\fR, \fBR_WIM\fR, and \fBR_TBR\fR can be used as indices to refer to
 758 the corresponding special registers. For SPARC V9 (64-bit) controlling
 759 processes, the predefined constants \fBR_CCR\fR, \fBR_ASI\fR, and \fBR_FPRS\fR
 760 can be used as indices to refer to the corresponding special registers.
 761 .RE
 762 
 763 .sp
 764 .ne 2
 765 .na
 766 \fBx86 (32-bit)\fR
 767 .ad
 768 .RS 21n
 769 For 32-bit x86 processes, the predefined constants listed belowcan be used as
 770 indices to refer to the corresponding registers.
 771 .sp
 772 .in +2
 773 .nf
 774 SS
 775 UESP
 776 EFL
 777 CS
 778 EIP
 779 ERR
 780 TRAPNO
 781 EAX
 782 ECX
 783 EDX
 784 EBX
 785 ESP
 786 EBP
 787 ESI
 788 EDI
 789 DS
 790 ES
 791 GS
 792 .fi
 793 .in -2
 794 
 795 The preceding constants are listed in \fB<sys/regset.h>\fR\&.
 796 .sp
 797 Note that a 32-bit process can run on an x86 64-bit system, using the constants
 798 listed above.
 799 .RE
 800 
 801 .sp
 802 .ne 2
 803 .na
 804 \fBx86 (64-bit)\fR
 805 .ad
 806 .RS 21n
 807 To read the registers of a 32- \fBor\fR a 64-bit process, a 64-bit x86 process
 808 should use the predefined constants listed below.
 809 .sp
 810 .in +2
 811 .nf
 812 REG_GSBASE
 813 REG_FSBASE
 814 REG_DS
 815 REG_ES
 816 REG_GS
 817 REG_FS
 818 REG_SS
 819 REG_RSP
 820 REG_RFL
 821 REG_CS
 822 REG_RIP
 823 REG_ERR
 824 REG_TRAPNO
 825 REG_RAX
 826 REG_RCX
 827 REG_RDX
 828 REG_RBX
 829 REG_RBP
 830 REG_RSI
 831 REG_RDI
 832 REG_R8
 833 REG_R9
 834 REG_R10
 835 REG_R11
 836 REG_R12
 837 REG_R13
 838 REG_R14
 839 REG_R15
 840 .fi
 841 .in -2
 842 
 843 The preceding constants are listed in \fB<sys/regset.h>\fR\&.
 844 .RE
 845 
 846 .sp
 847 .LP
 848 \fBpr_fpreg\fR is a structure holding the contents of the floating-point
 849 registers.
 850 .sp
 851 .LP
 852 SPARC registers, both general and floating-point, as seen by a 64-bit
 853 controlling process are the V9 versions of the registers, even if the target
 854 process is a 32-bit (V8) process. V8 registers are a subset of the V9
 855 registers.
 856 .sp
 857 .LP
 858 If the lwp is not stopped, all register values are undefined.
 859 .SS "psinfo"
 860 .LP
 861 Contains miscellaneous information about the process and the representative lwp
 862 needed by the \fBps\fR(1) command. \fBpsinfo\fR remains accessible after a
 863 process becomes a \fIzombie\fR. The file contains a \fBpsinfo\fR structure
 864 which contains an embedded \fBlwpsinfo\fR structure for the representative lwp,
 865 as follows:
 866 .sp
 867 .in +2
 868 .nf
 869 typedef struct psinfo {
 870     int pr_flag;             /* process flags (DEPRECATED: see below) */
 871     int pr_nlwp;             /* number of active lwps in the process */
 872     int pr_nzomb;            /* number of zombie lwps in the process */
 873     pid_t pr_pid;            /* process id */
 874     pid_t pr_ppid;           /* process id of parent */
 875     pid_t pr_pgid;           /* process id of process group leader */
 876     pid_t pr_sid;            /* session id */
 877     uid_t pr_uid;            /* real user id */
 878     uid_t pr_euid;           /* effective user id */
 879     gid_t pr_gid;            /* real group id */
 880     gid_t pr_egid;           /* effective group id */
 881     uintptr_t pr_addr;       /* address of process */
 882     size_t pr_size;          /* size of process image in Kbytes */
 883     size_t pr_rssize;        /* resident set size in Kbytes */
 884     dev_t pr_ttydev;         /* controlling tty device (or PRNODEV) */
 885     ushort_t pr_pctcpu;      /* % of recent cpu time used by all lwps */
 886     ushort_t pr_pctmem;      /* % of system memory used by process */
 887     timestruc_t pr_start;    /* process start time, from the epoch */
 888     timestruc_t pr_time;     /* cpu time for this process */
 889     timestruc_t pr_ctime;    /* cpu time for reaped children */
 890     char pr_fname[PRFNSZ];   /* name of exec'ed file */
 891     char pr_psargs[PRARGSZ]; /* initial characters of arg list */
 892     int pr_wstat;            /* if zombie, the wait() status */
 893     int pr_argc;             /* initial argument count */
 894     uintptr_t pr_argv;       /* address of initial argument vector */
 895     uintptr_t pr_envp;       /* address of initial environment vector */
 896     char pr_dmodel;          /* data model of the process */
 897     taskid_t pr_taskid;      /* task id */
 898     projid_t pr_projid;      /* project id */
 899     poolid_t pr_poolid;      /* pool id */
 900     zoneid_t pr_zoneid;      /* zone id */
 901     ctid_t pr_contract;      /* process contract id */
 902     lwpsinfo_t pr_lwp;       /* information for representative lwp */
 903 } psinfo_t;
 904 .fi
 905 .in -2
 906 
 907 .sp
 908 .LP
 909 Some of the entries in \fBpsinfo\fR, such as \fBpr_addr\fR, refer to internal
 910 kernel data structures and should not be expected to retain their meanings
 911 across different versions of the operating system.
 912 .sp
 913 .LP
 914 \fBpsinfo_t.pr_flag\fR is a deprecated interface that should no longer be used.
 915 Applications currently relying on the \fBSSYS\fR bit in \fBpr_flag\fR should
 916 migrate to checking \fBPR_ISSYS\fR in the \fBpstatus\fR structure's
 917 \fBpr_flags\fR field.
 918 .sp
 919 .LP
 920 \fBpr_pctcpu\fR and \fBpr_pctmem\fR are 16-bit binary fractions in the range
 921 0.0 to 1.0 with the binary point to the right of the high-order bit (1.0 ==
 922 0x8000). \fBpr_pctcpu\fR is the summation over all lwps in the process.
 923 .sp
 924 .LP
 925 \fBpr_lwp\fR contains the \fBps\fR(1) information for the representative lwp.
 926 If the process is a \fIzombie\fR, \fBpr_nlwp\fR, \fBpr_nzomb\fR, and
 927 \fBpr_lwp.pr_lwpid\fR are zero and the other fields of \fBpr_lwp\fR are
 928 undefined:
 929 .sp
 930 .in +2
 931 .nf
 932 typedef struct lwpsinfo {
 933     int pr_flag;             /* lwp flags (DEPRECATED: see below) */
 934     id_t pr_lwpid;           /* lwp id */
 935     uintptr_t pr_addr;       /* internal address of lwp */
 936     uintptr_t pr_wchan;      /* wait addr for sleeping lwp */
 937     char pr_stype;           /* synchronization event type */
 938     char pr_state;           /* numeric lwp state */
 939     char pr_sname;           /* printable character for pr_state */
 940     char pr_nice;            /* nice for cpu usage */
 941     short pr_syscall;        /* system call number (if in syscall) */
 942     char pr_oldpri;          /* pre-SVR4, low value is high priority */
 943     char pr_cpu;             /* pre-SVR4, cpu usage for scheduling */
 944     int pr_pri;              /* priority, high value = high priority */
 945     ushort_t pr_pctcpu;      /* % of recent cpu time used by this lwp */
 946     timestruc_t pr_start;    /* lwp start time, from the epoch */
 947     timestruc_t pr_time;     /* cpu time for this lwp */
 948     char pr_clname[PRCLSZ];  /* scheduling class name */
 949     char pr_name[PRFNSZ];    /* name of system lwp */
 950     processorid_t pr_onpro;  /* processor which last ran this lwp */
 951     processorid_t pr_bindpro;/* processor to which lwp is bound */
 952     psetid_t pr_bindpset;    /* processor set to which lwp is bound */
 953     lgrp_id_t pr_lgrp         /* home lgroup */
 954 } lwpsinfo_t;
 955 .fi
 956 .in -2
 957 
 958 .sp
 959 .LP
 960 Some of the entries in \fBlwpsinfo\fR, such as \fBpr_addr\fR, \fBpr_wchan\fR,
 961 \fBpr_stype\fR, \fBpr_state\fR, and \fBpr_name\fR, refer to internal kernel
 962 data structures and should not be expected to retain their meanings across
 963 different versions of the operating system.
 964 .sp
 965 .LP
 966 \fBlwpsinfo_t.pr_flag\fR is a deprecated interface that should no longer be
 967 used.
 968 .sp
 969 .LP
 970 \fBpr_pctcpu\fR is a 16-bit binary fraction, as described above. It represents
 971 the \fBCPU\fR time used by the specific lwp. On a multi-processor machine, the
 972 maximum value is 1/N, where N is the number of \fBCPU\fRs.
 973 .sp
 974 .LP
 975 \fBpr_contract\fR is the id of the process contract of which the process is a
 976 member. See \fBcontract\fR(4) and \fBprocess\fR(4).
 977 .SS "cred"
 978 .LP
 979 Contains a description of the credentials associated with the process:
 980 .sp
 981 .in +2
 982 .nf
 983 typedef struct prcred {
 984         uid_t pr_euid;      /* effective user id */
 985         uid_t pr_ruid;      /* real user id */
 986         uid_t pr_suid;      /* saved user id (from exec) */
 987         gid_t pr_egid;      /* effective group id */
 988         gid_t pr_rgid;      /* real group id */
 989         gid_t pr_sgid;      /* saved group id (from exec) */
 990         int pr_ngroups;     /* number of supplementary groups */
 991         gid_t pr_groups[1]; /* array of supplementary groups */
 992 } prcred_t;
 993 .fi
 994 .in -2
 995 .sp
 996 
 997 .sp
 998 .LP
 999 The array of associated supplementary groups in \fBpr_groups\fR is of variable
1000 length; the \fBcred\fR file contains all of the supplementary groups.
1001 \fBpr_ngroups\fR indicates the number of supplementary groups. (See also the
1002 \fBPCSCRED\fR and \fBPCSCREDX\fR control operations.)
1003 .SS "priv"
1004 .LP
1005 Contains a description of the privileges associated with the process:
1006 .sp
1007 .in +2
1008 .nf
1009 typedef struct prpriv {
1010      uint32_t        pr_nsets;      /* number of privilege set */
1011      uint32_t        pr_setsize;    /* size of privilege set */
1012      uint32_t        pr_infosize;   /* size of supplementary data */
1013      priv_chunk_t    pr_sets[1];    /* array of sets */
1014 } prpriv_t;
1015 .fi
1016 .in -2
1017 
1018 .sp
1019 .LP
1020 The actual dimension of the \fBpr_sets\fR[] field is
1021 .sp
1022 .in +2
1023 .nf
1024 pr_sets[pr_nsets][pr_setsize]
1025 .fi
1026 .in -2
1027 
1028 .sp
1029 .LP
1030 which is followed by additional information about the process state
1031 \fBpr_infosize\fR bytes in size.
1032 .sp
1033 .LP
1034 The full size of the structure can be computed using
1035 \fBPRIV_PRPRIV_SIZE\fR(\fBprpriv_t *\fR).
1036 .SS "secflags"
1037 .LP
1038 This file contains the security-flags of the process.  It contains a
1039 description of the security flags associated with the process.
1040 .sp
1041 .in +2
1042 .nf
1043 typedef struct prsecflags {
1044         uint32_t pr_version;            /* ABI Versioning of this structure */
1045         secflagset_t pr_effective;      /* Effective flags */
1046         secflagset_t pr_inherit;        /* Inheritable flags */
1047         secflagset_t pr_lower;          /* Lower flags */
1048         secflagset_t pr_upper;          /* Upper flags */
1049 } prsecflags_t;
1050 .in -2
1051 
1052 .sp
1053 .LP
1054 The \fBpr_version\fR field is a version number for the structure, currently
1055 \fBPRSECFLAGS_VERSION_1\fR.
1056 .SS "sigact"
1057 .LP
1058 Contains an array of \fBsigaction structures\fR describing the current
1059 dispositions of all signals associated with the traced process (see
1060 \fBsigaction\fR(2)). Signal numbers are displaced by 1 from array indices, so
1061 that the action for signal number \fIn\fR appears in position \fIn\fR-1 of the
1062 array.
1063 .SS "auxv"
1064 .LP
1065 Contains the initial values of the process's aux vector in an array of
1066 \fBauxv_t\fR structures (see \fB<sys/auxv.h>\fR). The values are those that
1067 were passed by the operating system as startup information to the dynamic
1068 linker.
1069 .SS "ldt"
1070 .LP
1071 This file exists only on x86-based machines. It is non-empty only if the
1072 process has established a local descriptor table (\fBLDT\fR). If non-empty, the
1073 file contains the array of currently active \fBLDT\fR entries in an array of
1074 elements of type \fBstruct ssd\fR, defined in \fB<sys/sysi86.h>\fR, one element
1075 for each active \fBLDT\fR entry.
1076 .SS "map, xmap"
1077 .LP
1078 Contain information about the virtual address map of the process. The map file
1079 contains an array of \fBprmap\fR structures while the xmap file contains an
1080 array of \fBprxmap\fR structures. Each structure describes a contiguous virtual
1081 address region in the address space of the traced process:
1082 .sp
1083 .in +2
1084 .nf
1085 typedef struct prmap {
1086         uintptr_tpr_vaddr;         /* virtual address of mapping */
1087         size_t pr_size;            /* size of mapping in bytes */
1088         char pr_mapname[PRMAPSZ];  /* name in /proc/pid/object */
1089         offset_t pr_offset;        /* offset into mapped object, if any */
1090         int pr_mflags;             /* protection and attribute flags */
1091         int pr_pagesize;           /* pagesize for this mapping in bytes */
1092         int pr_shmid;              /* SysV shared memory identifier */
1093 } prmap_t;
1094 .fi
1095 .in -2
1096 .sp
1097 
1098 .sp
1099 .in +2
1100 .nf
1101 typedef struct prxmap {
1102         uintptr_t pr_vaddr;        /* virtual address of mapping */
1103         size_t pr_size;            /* size of mapping in bytes */
1104         char pr_mapname[PRMAPSZ];  /* name in /proc/pid/object */
1105         offset_t pr_offset;        /* offset into mapped object, if any */
1106         int pr_mflags;             /* protection and attribute flags */
1107         int pr_pagesize;           /* pagesize for this mapping in bytes */
1108         int pr_shmid;              /* SysV shared memory identifier */
1109         dev_t pr_dev;              /* device of mapped object, if any */
1110         uint64_t pr_ino;           /* inode of mapped object, if any */
1111         size_t pr_rss;             /* pages of resident memory */
1112         size_t pr_anon;            /* pages of resident anonymous memory */
1113         size_t pr_locked;          /* pages of locked memory */
1114         uint64_t pr_hatpagesize;   /* pagesize of mapping */
1115 } prxmap_t;
1116 .fi
1117 .in -2
1118 .sp
1119 
1120 .sp
1121 .LP
1122 \fBpr_vaddr\fR is the virtual address of the mapping within the traced process
1123 and \fBpr_size\fR is its size in bytes. \fBpr_mapname\fR, if it does not
1124 contain a null string, contains the name of a file in the \fBobject\fR
1125 directory (see below) that can be opened read-only to obtain a file descriptor
1126 for the mapped file associated with the mapping. This enables a debugger to
1127 find object file symbol tables without having to know the real path names of
1128 the executable file and shared libraries of the process. \fBpr_offset\fR is the
1129 64-bit offset within the mapped file (if any) to which the virtual address is
1130 mapped.
1131 .sp
1132 .LP
1133 \fBpr_mflags\fR is a bit-mask of protection and attribute flags:
1134 .sp
1135 .ne 2
1136 .na
1137 \fB\fBMA_READ\fR\fR
1138 .ad
1139 .RS 17n
1140 mapping is readable by the traced process.
1141 .RE
1142 
1143 .sp
1144 .ne 2
1145 .na
1146 \fB\fBMA_WRITE\fR\fR
1147 .ad
1148 .RS 17n
1149 mapping is writable by the traced process.
1150 .RE
1151 
1152 .sp
1153 .ne 2
1154 .na
1155 \fB\fBMA_EXEC\fR\fR
1156 .ad
1157 .RS 17n
1158 mapping is executable by the traced process.
1159 .RE
1160 
1161 .sp
1162 .ne 2
1163 .na
1164 \fB\fBMA_SHARED\fR\fR
1165 .ad
1166 .RS 17n
1167 mapping changes are shared by the mapped object.
1168 .RE
1169 
1170 .sp
1171 .ne 2
1172 .na
1173 \fB\fBMA_ISM\fR\fR
1174 .ad
1175 .RS 17n
1176 mapping is intimate shared memory (shared MMU resources)
1177 .RE
1178 
1179 .sp
1180 .ne 2
1181 .na
1182 \fB\fBMAP_NORESERVE\fR\fR
1183 .ad
1184 .RS 17n
1185 mapping does not have swap space reserved (mapped with MAP_NORESERVE)
1186 .RE
1187 
1188 .sp
1189 .ne 2
1190 .na
1191 \fB\fBMA_SHM\fR\fR
1192 .ad
1193 .RS 17n
1194 mapping System V shared memory
1195 .RE
1196 
1197 .sp
1198 .LP
1199 A contiguous area of the address space having the same underlying mapped object
1200 may appear as multiple mappings due to varying read, write, and execute
1201 attributes. The underlying mapped object does not change over the range of a
1202 single mapping. An \fBI/O\fR operation to a mapping marked \fBMA_SHARED\fR
1203 fails if applied at a virtual address not corresponding to a valid page in the
1204 underlying mapped object. A write to a \fBMA_SHARED\fR mapping that is not
1205 marked \fBMA_WRITE\fR fails. Reads and writes to private mappings always
1206 succeed. Reads and writes to unmapped addresses fail.
1207 .sp
1208 .LP
1209 \fBpr_pagesize\fR is the page size for the mapping, currently always the system
1210 pagesize.
1211 .sp
1212 .LP
1213 \fBpr_shmid\fR is the shared memory identifier, if any, for the mapping. Its
1214 value is \fB\(mi1\fR if the mapping is not System V shared memory. See
1215 \fBshmget\fR(2).
1216 .sp
1217 .LP
1218 \fBpr_dev\fR is the device of the mapped object, if any, for the mapping. Its
1219 value is \fBPRNODEV\fR (-1) if the mapping does not have a device.
1220 .sp
1221 .LP
1222 \fBpr_ino\fR is the inode of the mapped object, if any, for the mapping. Its
1223 contents are only valid if \fBpr_dev\fR is not \fBPRNODEV.\fR
1224 .sp
1225 .LP
1226 \fBpr_rss\fR is the number of resident pages of memory for the mapping. The
1227 number of resident bytes for the mapping may be determined by multiplying
1228 \fBpr_rss\fR by the page size given by \fBpr_pagesize.\fR
1229 .sp
1230 .LP
1231 \fBpr_anon\fR is the number of resident anonymous memory pages (pages which are
1232 private to this process) for the mapping.
1233 .sp
1234 .LP
1235 \fBpr_locked\fR is the number of locked pages for the mapping. Pages which are
1236 locked are always resident in memory.
1237 .sp
1238 .LP
1239 \fBpr_hatpagesize\fR is the size, in bytes, of the \fBHAT\fR (\fBMMU\fR)
1240 translation for the mapping. \fBpr_hatpagesize\fR may be different than
1241 \fBpr_pagesize.\fR The possible values are hardware architecture specific, and
1242 may change over a mapping's lifetime.
1243 .SS "rmap"
1244 .LP
1245 Contains information about the reserved address ranges of the process. The file
1246 contains an array of \fBprmap\fR structures, as defined above for the \fBmap\fR
1247 file. Each structure describes a contiguous virtual address region in the
1248 address space of the traced process that is reserved by the system in the sense
1249 that an \fBmmap\fR(2) system call that does not specify \fBMAP_FIXED\fR will
1250 not use any part of it for the new mapping. Examples of such reservations
1251 include the address ranges reserved for the process stack and the individual
1252 thread stacks of a multi-threaded process.
1253 .SS "cwd"
1254 .LP
1255 A symbolic link to the process's current working directory. See \fBchdir\fR(2).
1256 A \fBreadlink\fR(2) of \fB/proc/\fIpid\fR/cwd\fR yields a null string. However,
1257 it can be opened, listed, and searched as a directory, and can be the target of
1258 \fBchdir\fR(2).
1259 .SS "root"
1260 .LP
1261 A symbolic link to the process's root directory.
1262 \fB/proc/\fR\fIpid\fR\fB/root\fR can differ from the system root directory if
1263 the process or one of its ancestors executed \fBchroot\fR(2) as super user. It
1264 has the same semantics as \fB/proc/\fR\fIpid\fR\fB/cwd\fR.
1265 .SS "fd"
1266 .LP
1267 A directory containing references to the open files of the process. Each entry
1268 is a decimal number corresponding to an open file descriptor in the process.
1269 .sp
1270 .LP
1271 If an entry refers to a regular file, it can be opened with normal file system
1272 semantics but, to ensure that the controlling process cannot gain greater
1273 access than the controlled process, with no file access modes other than its
1274 read/write open modes in the controlled process. If an entry refers to a
1275 directory, it can be accessed with the same semantics as
1276 \fB/proc/\fIpid\fR/cwd\fR. An attempt to open any other type of entry fails
1277 with \fBEACCES\fR.
1278 .SS "object"
1279 .LP
1280 A directory containing read-only files with names corresponding to the
1281 \fBpr_mapname\fR entries in the \fBmap\fR and \fBpagedata\fR files. Opening
1282 such a file yields a file descriptor for the underlying mapped file associated
1283 with an address-space mapping in the process. The file name \fBa.out\fR appears
1284 in the directory as an alias for the process's executable file.
1285 .sp
1286 .LP
1287 The \fBobject\fR directory makes it possible for a controlling process to gain
1288 access to the object file and any shared libraries (and consequently the symbol
1289 tables) without having to know the actual path names of the executable files.
1290 .SS "path"
1291 .LP
1292 A directory containing symbolic links to files opened by the process. The
1293 directory includes one entry for \fBcwd\fR and \fBroot\fR. The directory also
1294 contains a numerical entry for each file descriptor in the \fBfd\fR directory,
1295 and entries matching those in the \fBobject\fR directory. If this information
1296 is not available, any attempt to read the contents of the symbolic link will
1297 fail. This is most common for files that do not exist in the filesystem
1298 namespace (such as \fBFIFO\fRs and sockets), but can also happen for regular
1299 files. For the file descriptor entries, the path may be different from the one
1300 used by the process to open the file.
1301 .SS "pagedata"
1302 .LP
1303 Opening the page data file enables tracking of address space references and
1304 modifications on a per-page basis.
1305 .sp
1306 .LP
1307 A \fBread\fR(2) of the page data file descriptor returns structured page data
1308 and atomically clears the page data maintained for the file by the system. That
1309 is to say, each read returns data collected since the last read; the first read
1310 returns data collected since the file was opened. When the call completes, the
1311 read buffer contains the following structure as its header and thereafter
1312 contains a number of section header structures and associated byte arrays that
1313 must be accessed by walking linearly through the buffer.
1314 .sp
1315 .in +2
1316 .nf
1317 typedef struct prpageheader {
1318     timestruc_t pr_tstamp; /* real time stamp, time of read() */
1319     ulong_t pr_nmap;       /* number of address space mappings */
1320     ulong_t pr_npage;      /* total number of pages */
1321 } prpageheader_t;
1322 .fi
1323 .in -2
1324 
1325 .sp
1326 .LP
1327 The header is followed by \fBpr_nmap prasmap\fR structures and associated data
1328 arrays. The \fBprasmap\fR structure contains the following elements:
1329 .sp
1330 .in +2
1331 .nf
1332 typedef struct prasmap {
1333     uintptr_t pr_vaddr;        /* virtual address of mapping */
1334     ulong_t pr_npage;          /* number of pages in mapping */
1335     char pr_mapname[PRMAPSZ];  /* name in /proc/pid/object */
1336     offset_t pr_offset;        /* offset into mapped object, if any */
1337     int pr_mflags;             /* protection and attribute flags */
1338     int pr_pagesize;           /* pagesize for this mapping in bytes */
1339     int pr_shmid;              /* SysV shared memory identifier */
1340 } prasmap_t;
1341 .fi
1342 .in -2
1343 
1344 .sp
1345 .LP
1346 Each section header is followed by \fBpr_npage\fR bytes, one byte for each page
1347 in the mapping, plus 0-7 null bytes at the end so that the next \fBprasmap\fR
1348 structure begins on an eight-byte aligned boundary. Each data byte may contain
1349 these flags:
1350 .sp
1351 .ne 2
1352 .na
1353 \fB\fBPG_REFERENCED\fR\fR
1354 .ad
1355 .RS 17n
1356 page has been referenced.
1357 .RE
1358 
1359 .sp
1360 .ne 2
1361 .na
1362 \fB\fBPG_MODIFIED\fR\fR
1363 .ad
1364 .RS 17n
1365 page has been modified.
1366 .RE
1367 
1368 .sp
1369 .LP
1370 If the read buffer is not large enough to contain all of the page data, the
1371 read fails with \fBE2BIG\fR and the page data is not cleared. The required size
1372 of the read buffer can be determined through \fBfstat\fR(2). Application of
1373 \fBlseek\fR(2) to the page data file descriptor is ineffective; every read
1374 starts from the beginning of the file. Closing the page data file descriptor
1375 terminates the system overhead associated with collecting the data.
1376 .sp
1377 .LP
1378 More than one page data file descriptor for the same process can be opened, up
1379 to a system-imposed limit per traced process. A read of one does not affect the
1380 data being collected by the system for the others. An open of the page data
1381 file will fail with \fBENOMEM\fR if the system-imposed limit would be exceeded.
1382 .SS "watch"
1383 .LP
1384 Contains an array of \fBprwatch\fR structures, one for each watched area
1385 established by the \fBPCWATCH\fR control operation. See \fBPCWATCH\fR for
1386 details.
1387 .SS "usage"
1388 .LP
1389 Contains process usage information described by a \fBprusage\fR structure which
1390 contains at least the following fields:
1391 .sp
1392 .in +2
1393 .nf
1394 typedef struct prusage {
1395     id_t pr_lwpid;           /* lwp id.  0: process or defunct */
1396     int pr_count;            /* number of contributing lwps */
1397     timestruc_t pr_tstamp;   /* real time stamp, time of read() */
1398     timestruc_t pr_create;   /* process/lwp creation time stamp */
1399     timestruc_t pr_term;     /* process/lwp termination time stamp */
1400     timestruc_t pr_rtime;    /* total lwp real (elapsed) time */
1401     timestruc_t pr_utime;    /* user level CPU time */
1402     timestruc_t pr_stime;    /* system call CPU time */
1403     timestruc_t pr_ttime;    /* other system trap CPU time */
1404     timestruc_t pr_tftime;   /* text page fault sleep time */
1405     timestruc_t pr_dftime;   /* data page fault sleep time */
1406     timestruc_t pr_kftime;   /* kernel page fault sleep time */
1407     timestruc_t pr_ltime;    /* user lock wait sleep time */
1408     timestruc_t pr_slptime;  /* all other sleep time */
1409     timestruc_t pr_wtime;    /* wait-cpu (latency) time */
1410     timestruc_t pr_stoptime; /* stopped time */
1411     ulong_t pr_minf;         /* minor page faults */
1412     ulong_t pr_majf;         /* major page faults */
1413     ulong_t pr_nswap;        /* swaps */
1414     ulong_t pr_inblk;        /* input blocks */
1415     ulong_t pr_oublk;        /* output blocks */
1416     ulong_t pr_msnd;         /* messages sent */
1417     ulong_t pr_mrcv;         /* messages received */
1418     ulong_t pr_sigs;         /* signals received */
1419     ulong_t pr_vctx;         /* voluntary context switches */
1420     ulong_t pr_ictx;         /* involuntary context switches */
1421     ulong_t pr_sysc;         /* system calls */
1422     ulong_t pr_ioch;         /* chars read and written */
1423 } prusage_t;
1424 .fi
1425 .in -2
1426 
1427 .sp
1428 .LP
1429 Microstate accounting is now continuously enabled. While this information was
1430 previously an estimate, if microstate accounting were not enabled, the current
1431 information is now never an estimate represents time the process has spent in
1432 various states.
1433 .SS "lstatus"
1434 .LP
1435 Contains a \fBprheader\fR structure followed by an array of \fBlwpstatus\fR
1436 structures, one for each active lwp in the process (see also
1437 \fB/proc/\fR\fIpid\fR\fB/lwp/\fR\fIlwpid\fR/\fBlwpstatus\fR, below). The
1438 \fBprheader\fR structure describes the number and size of the array entries
1439 that follow.
1440 .sp
1441 .in +2
1442 .nf
1443 typedef struct prheader {
1444     long pr_nent;        /* number of entries */
1445     size_t pr_entsize;   /* size of each entry, in bytes */
1446 } prheader_t;
1447 .fi
1448 .in -2
1449 
1450 .sp
1451 .LP
1452 The \fBlwpstatus\fR structure may grow by the addition of elements at the end
1453 in future releases of the system. Programs must use \fBpr_entsize\fR in the
1454 file header to index through the array. These comments apply to all \fB/proc\fR
1455 files that include a \fBprheader\fR structure (\fBlpsinfo\fR and \fBlusage\fR,
1456 below).
1457 .SS "lpsinfo"
1458 .LP
1459 Contains a \fBprheader\fR structure followed by an array of \fBlwpsinfo\fR
1460 structures, one for eachactive and zombie lwp in the process. See also
1461 \fB/proc/\fR\fIpid\fR\fB/lwp/\fR\fIlwpid\fR/\fBlwpsinfo\fR, below.
1462 .SS "lusage"
1463 .LP
1464 Contains a \fBprheader\fR structure followed by an array of \fBprusage\fR
1465 structures, one for each active lwp in the process, plus an additional element
1466 at the beginning that contains the summation over all defunct lwps (lwps that
1467 once existed but no longer exist in the process). Excluding the \fBpr_lwpid\fR,
1468 \fBpr_tstamp\fR, \fBpr_create\fR, and \fBpr_term\fR entries, the entry-by-entry
1469 summation over all these structures is the definition of the process usage
1470 information obtained from the \fBusage\fR file. (See also
1471 \fB/proc/\fR\fIpid\fR\fB/lwp/\fR\fIlwpid\fR/\fBlwpusage\fR, below.)
1472 .SS "lwp"
1473 .LP
1474 A directory containing entries each of which names an active or zombie lwp
1475 within the process. These entries are themselves directories containing
1476 additional files as described below. Only the \fBlwpsinfo\fR file exists in the
1477 directory of a zombie lwp.
1478 .SH STRUCTURE OF \fB/proc/\fR\fIpid\fR\fB/lwp/\fR\fIlwpid\fR
1479 .LP
1480 A given directory \fB/proc/\fR\fIpid\fR\fB/lwp/\fR\fIlwpid\fR contains the
1481 following entries:
1482 .SS "lwpctl"
1483 .LP
1484 Write-only control file. The messages written to this file affect the specific
1485 lwp rather than the representative lwp, as is the case for the process's
1486 \fBctl\fR file.
1487 .SS lwpname
1488 A buffer of \fBTHREAD_NAME_MAX\fR bytes representing the LWP name; the buffer is
1489 zero-filled if the thread name is shorter than the buffer. If no thread name is
1490 set, the buffer contains the empty string. A read with a buffer shorter than
1491 \fBTHREAD_NAME_MAX\fR bytes is not guaranteed to be NUL-terminated.  Writing to
1492 this file will set the LWP name for the specific lwp.  This file may not be
1493 present in older operating system versions. \fBTHREAD_NAME_MAX\fR may increase
1494 in the future; clients should be prepared for this.
1495 .SS "lwpstatus"
1496 .LP
1497 lwp-specific state information. This file contains the \fBlwpstatus\fR
1498 structure for the specific lwp as described above for the representative lwp in
1499 the process's \fBstatus\fR file.
1500 .SS "lwpsinfo"
1501 .LP
1502 lwp-specific \fBps\fR(1) information. This file contains the \fBlwpsinfo\fR
1503 structure for the specific lwp as described above for the representative lwp in
1504 the process's \fBpsinfo\fR file. The \fBlwpsinfo\fR file remains accessible
1505 after an lwp becomes a zombie.
1506 .SS "lwpusage"
1507 .LP
1508 This file contains the \fBprusage\fR structure for the specific lwp as
1509 described above for the process's \fBusage\fR file.
1510 .SS "gwindows"
1511 .LP
1512 This file exists only on SPARC based machines. If it is non-empty, it contains
1513 a \fBgwindows_t\fR structure, defined in \fB<sys/regset.h>\fR, with the values
1514 of those SPARC register windows that could not be stored on the stack when the
1515 lwp stopped. Conditions under which register windows are not stored on the
1516 stack are: the stack pointer refers to nonexistent process memory or the stack
1517 pointer is improperly aligned. If the lwp is not stopped or if there are no
1518 register windows that could not be stored on the stack, the file is empty (the
1519 usual case).
1520 .SS "xregs"
1521 .LP
1522 Extra state registers. The extra state register set is architecture dependent;
1523 this file is empty if the system does not support extra state registers. If the
1524 file is non-empty, it contains an architecture dependent structure of type
1525 \fBprxregset_t\fR, defined in \fB<procfs.h>\fR, with the values of the lwp's
1526 extra state registers. If the lwp is not stopped, all register values are
1527 undefined. See also the \fBPCSXREG\fR control operation, below.
1528 .SS "asrs"
1529 .LP
1530 This file exists only for 64-bit SPARC V9 processes. It contains an
1531 \fBasrset_t\fR structure, defined in <\fBsys/regset.h\fR>, containing the
1532 values of the lwp's platform-dependent ancillary state registers. If the lwp is
1533 not stopped, all register values are undefined. See also the \fBPCSASRS\fR
1534 control operation, below.
1535 .SS "spymaster"
1536 .LP
1537 For an agent lwp (see \fBPCAGENT\fR), this file contains a \fBpsinfo_t\fR
1538 structure that corresponds to the process that created the agent lwp at the
1539 time the agent was created. This structure is identical to that retrieved via
1540 the \fBpsinfo\fR file, with one modification: the \fBpr_time\fR field does not
1541 correspond to the CPU time for the process, but rather to the creation time of
1542 the agent lwp.
1543 .SS "templates"
1544 .LP
1545 A directory which contains references to the active templates for the lwp,
1546 named by the contract type. Changes made to an active template descriptor do
1547 not affect the original template which was activated, though they do affect the
1548 active template. It is not possible to activate an active template descriptor.
1549 See \fBcontract\fR(4).
1550 .SH CONTROL MESSAGES
1551 .LP
1552 Process state changes are effected through messages written to a process's
1553 \fBctl\fR file or to an individual lwp's \fBlwpctl\fR file. All control
1554 messages consist of a \fBlong\fR that names the specific operation followed by
1555 additional data containing the operand, if any.
1556 .sp
1557 .LP
1558 Multiple control messages may be combined in a single \fBwrite\fR(2) (or
1559 \fBwritev\fR(2)) to a control file, but no partial writes are permitted. That
1560 is, each control message, operation code plus operand, if any, must be
1561 presented in its entirety to the \fBwrite\fR(2) and not in pieces over several
1562 system calls. If a control operation fails, no subsequent operations contained
1563 in the same \fBwrite\fR(2) are attempted.
1564 .sp
1565 .LP
1566 Descriptions of the allowable control messages follow. In all cases, writing a
1567 message to a control file for a process or lwp that has terminated elicits the
1568 error \fBENOENT\fR.
1569 .SS "PCSTOP PCDSTOP PCWSTOP PCTWSTOP"
1570 .LP
1571 When applied to the process control file, \fBPCSTOP\fR directs all lwps to stop
1572 and waits for them to stop, \fBPCDSTOP\fR directs all lwps to stop without
1573 waiting for them to stop, and \fBPCWSTOP\fR simply waits for all lwps to stop.
1574 When applied to an lwp control file, \fBPCSTOP\fR directs the specific lwp to
1575 stop and waits until it has stopped, \fBPCDSTOP\fR directs the specific lwp to
1576 stop without waiting for it to stop, and \fBPCWSTOP\fR simply waits for the
1577 specific lwp to stop. When applied to an lwp control file, \fBPCSTOP\fR and
1578 \fBPCWSTOP\fR complete when the lwp stops on an event of interest, immediately
1579 if already so stopped; when applied to the process control file, they complete
1580 when every lwp has stopped either on an event of interest or on a
1581 \fBPR_SUSPENDED\fR stop.
1582 .sp
1583 .LP
1584 \fBPCTWSTOP\fR is identical to \fBPCWSTOP\fR except that it enables the
1585 operation to time out, to avoid waiting forever for a process or lwp that may
1586 never stop on an event of interest. \fBPCTWSTOP\fR takes a \fBlong\fR operand
1587 specifying a number of milliseconds; the wait will terminate successfully after
1588 the specified number of milliseconds even if the process or lwp has not
1589 stopped; a timeout value of zero makes the operation identical to
1590 \fBPCWSTOP\fR.
1591 .sp
1592 .LP
1593 An ``event of interest'' is either a \fBPR_REQUESTED\fR stop or a stop that has
1594 been specified in the process's tracing flags (set by \fBPCSTRACE\fR,
1595 \fBPCSFAULT\fR, \fBPCSENTRY\fR, and \fBPCSEXIT\fR). \fBPR_JOBCONTROL\fR and
1596 \fBPR_SUSPENDED\fR stops are specifically not events of interest. (An lwp may
1597 stop twice due to a stop signal, first showing \fBPR_SIGNALLED\fR if the signal
1598 is traced and again showing \fBPR_JOBCONTROL\fR if the lwp is set running
1599 without clearing the signal.) If \fBPCSTOP\fR or \fBPCDSTOP\fR is applied to an
1600 lwp that is stopped, but not on an event of interest, the stop directive takes
1601 effect when the lwp is restarted by the competing mechanism. At that time, the
1602 lwp enters a \fBPR_REQUESTED\fR stop before executing any user-level code.
1603 .sp
1604 .LP
1605 A write of a control message that blocks is interruptible by a signal so that,
1606 for example, an \fBalarm\fR(2) can be set to avoid waiting forever for a
1607 process or lwp that may never stop on an event of interest. If \fBPCSTOP\fR is
1608 interrupted, the lwp stop directives remain in effect even though the
1609 \fBwrite\fR(2) returns an error. (Use of \fBPCTWSTOP\fR with a non-zero timeout
1610 is recommended over \fBPCWSTOP\fR with an \fBalarm\fR(2).)
1611 .sp
1612 .LP
1613 A system process (indicated by the \fBPR_ISSYS\fR flag) never executes at user
1614 level, has no user-level address space visible through \fB/proc\fR, and cannot
1615 be stopped. Applying one of these operations to a system process or any of its
1616 lwps elicits the error \fBEBUSY\fR.
1617 .SS "PCRUN"
1618 .LP
1619 Make an lwp runnable again after a stop. This operation takes a \fBlong\fR
1620 operand containing zero or more of the following flags:
1621 .sp
1622 .ne 2
1623 .na
1624 \fB\fBPRCSIG\fR\fR
1625 .ad
1626 .RS 12n
1627 clears the current signal, if any (see \fBPCCSIG\fR).
1628 .RE
1629 
1630 .sp
1631 .ne 2
1632 .na
1633 \fB\fBPRCFAULT\fR\fR
1634 .ad
1635 .RS 12n
1636 clears the current fault, if any (see \fBPCCFAULT\fR).
1637 .RE
1638 
1639 .sp
1640 .ne 2
1641 .na
1642 \fB\fBPRSTEP\fR\fR
1643 .ad
1644 .RS 12n
1645 directs the lwp to execute a single machine instruction. On completion of the
1646 instruction, a trace trap occurs. If \fBFLTTRACE\fR is being traced, the lwp
1647 stops; otherwise, it is sent \fBSIGTRAP\fR. If \fBSIGTRAP\fR is being traced
1648 and is not blocked, the lwp stops. When the lwp stops on an event of interest,
1649 the single-step directive is cancelled, even if the stop occurs before the
1650 instruction is executed. This operation requires hardware and operating system
1651 support and may not be implemented on all processors. It is implemented on
1652 SPARC and x86-based machines.
1653 .RE
1654 
1655 .sp
1656 .ne 2
1657 .na
1658 \fB\fBPRSABORT\fR\fR
1659 .ad
1660 .RS 12n
1661 is meaningful only if the lwp is in a \fBPR_SYSENTRY\fR stop or is marked
1662 \fBPR_ASLEEP\fR; it instructs the lwp to abort execution of the system call
1663 (see \fBPCSENTRY\fR and \fBPCSEXIT\fR).
1664 .RE
1665 
1666 .sp
1667 .ne 2
1668 .na
1669 \fB\fBPRSTOP\fR\fR
1670 .ad
1671 .RS 12n
1672 directs the lwp to stop again as soon as possible after resuming execution (see
1673 \fBPCDSTOP\fR). In particular, if the lwp is stopped on \fBPR_SIGNALLED\fR or
1674 \fBPR_FAULTED\fR, the next stop will show \fBPR_REQUESTED\fR, no other stop
1675 will have intervened, and the lwp will not have executed any user-level code.
1676 .RE
1677 
1678 .sp
1679 .LP
1680 When applied to an lwp control file, \fBPCRUN\fR clears any outstanding
1681 directed-stop request and makes the specific lwp runnable. The operation fails
1682 with \fBEBUSY\fR if the specific lwp is not stopped on an event of interest or
1683 has not been directed to stop or if the agent lwp exists and this is not the
1684 agent lwp (see \fBPCAGENT\fR).
1685 .sp
1686 .LP
1687 When applied to the process control file, a representative lwp is chosen for
1688 the operation as described for \fB/proc/\fR\fIpid\fR\fB/status\fR. The
1689 operation fails with \fBEBUSY\fR if the representative lwp is not stopped on an
1690 event of interest or has not been directed to stop or if the agent lwp exists.
1691 If \fBPRSTEP\fR or \fBPRSTOP\fR was requested, the representative lwp is made
1692 runnable and its outstanding directed-stop request is cleared; otherwise all
1693 outstanding directed-stop requests are cleared and, if it was stopped on an
1694 event of interest, the representative lwp is marked \fBPR_REQUESTED\fR. If, as
1695 a consequence, all lwps are in the \fBPR_REQUESTED\fR or \fBPR_SUSPENDED\fR
1696 stop state, all lwps showing \fBPR_REQUESTED\fR are made runnable.
1697 .SS "PCSTRACE"
1698 .LP
1699 Define a set of signals to be traced in the process. The receipt of one of
1700 these signals by an lwp causes the lwp to stop. The set of signals is defined
1701 using an operand \fBsigset_t\fR contained in the control message. Receipt of
1702 \fBSIGKILL\fR cannot be traced; if specified, it is silently ignored.
1703 .sp
1704 .LP
1705 If a signal that is included in an lwp's held signal set (the signal mask) is
1706 sent to the lwp, the signal is not received and does not cause a stop until it
1707 is removed from the held signal set, either by the lwp itself or by setting the
1708 held signal set with \fBPCSHOLD\fR.
1709 .SS "PCCSIG"
1710 .LP
1711 The current signal, if any, is cleared from the specific or representative lwp.
1712 .SS "PCSSIG"
1713 .LP
1714 The current signal and its associated signal information for the specific or
1715 representative lwp are set according to the contents of the operand
1716 \fBsiginfo\fR structure (see \fB<sys/siginfo.h>\fR). If the specified signal
1717 number is zero, the current signal is cleared. The semantics of this operation
1718 are different from those of \fBkill\fR(2) in that the signal is delivered to
1719 the lwp immediately after execution is resumed (even if it is being blocked)
1720 and an additional \fBPR_SIGNALLED\fR stop does not intervene even if the signal
1721 is traced. Setting the current signal to \fBSIGKILL\fR terminates the process
1722 immediately.
1723 .SS "PCKILL"
1724 .LP
1725 If applied to the process control file, a signal is sent to the process with
1726 semantics identical to those of \fBkill\fR(2). If applied to an lwp control
1727 file, a directed signal is sent to the specific lwp. The signal is named in a
1728 \fBlong\fR operand contained in the message. Sending \fBSIGKILL\fR terminates
1729 the process immediately.
1730 .SS "PCUNKILL"
1731 .LP
1732 A signal is deleted, that is, it is removed from the set of pending signals. If
1733 applied to the process control file, the signal is deleted from the process's
1734 pending signals. If applied to an lwp control file, the signal is deleted from
1735 the lwp's pending signals. The current signal (if any) is unaffected. The
1736 signal is named in a \fBlong\fR operand in the control message. It is an error
1737 (\fBEINVAL\fR) to attempt to delete \fBSIGKILL\fR.
1738 .SS "PCSHOLD"
1739 .LP
1740 Set the set of held signals for the specific or representative lwp (signals
1741 whose delivery will be blocked if sent to the lwp). The set of signals is
1742 specified with a \fBsigset_t\fR operand. \fBSIGKILL\fR and \fBSIGSTOP\fR cannot
1743 be held; if specified, they are silently ignored.
1744 .SS "PCSFAULT"
1745 .LP
1746 Define a set of hardware faults to be traced in the process. On incurring one
1747 of these faults, an lwp stops. The set is defined via the operand
1748 \fBfltset_t\fR structure. Fault names are defined in \fB<sys/fault.h>\fR and
1749 include the following. Some of these may not occur on all processors; there may
1750 be processor-specific faults in addition to these.
1751 .sp
1752 .ne 2
1753 .na
1754 \fB\fBFLTILL\fR\fR
1755 .ad
1756 .RS 13n
1757 illegal instruction
1758 .RE
1759 
1760 .sp
1761 .ne 2
1762 .na
1763 \fB\fBFLTPRIV\fR\fR
1764 .ad
1765 .RS 13n
1766 privileged instruction
1767 .RE
1768 
1769 .sp
1770 .ne 2
1771 .na
1772 \fB\fBFLTBPT\fR\fR
1773 .ad
1774 .RS 13n
1775 breakpoint trap
1776 .RE
1777 
1778 .sp
1779 .ne 2
1780 .na
1781 \fB\fBFLTTRACE\fR\fR
1782 .ad
1783 .RS 13n
1784 trace trap (single-step)
1785 .RE
1786 
1787 .sp
1788 .ne 2
1789 .na
1790 \fB\fBFLTWATCH\fR\fR
1791 .ad
1792 .RS 13n
1793 watchpoint trap
1794 .RE
1795 
1796 .sp
1797 .ne 2
1798 .na
1799 \fB\fBFLTACCESS\fR\fR
1800 .ad
1801 .RS 13n
1802 memory access fault (bus error)
1803 .RE
1804 
1805 .sp
1806 .ne 2
1807 .na
1808 \fB\fBFLTBOUNDS\fR\fR
1809 .ad
1810 .RS 13n
1811 memory bounds violation
1812 .RE
1813 
1814 .sp
1815 .ne 2
1816 .na
1817 \fB\fBFLTIOVF\fR\fR
1818 .ad
1819 .RS 13n
1820 integer overflow
1821 .RE
1822 
1823 .sp
1824 .ne 2
1825 .na
1826 \fB\fBFLTIZDIV\fR\fR
1827 .ad
1828 .RS 13n
1829 integer zero divide
1830 .RE
1831 
1832 .sp
1833 .ne 2
1834 .na
1835 \fB\fBFLTFPE\fR\fR
1836 .ad
1837 .RS 13n
1838 floating-point exception
1839 .RE
1840 
1841 .sp
1842 .ne 2
1843 .na
1844 \fB\fBFLTSTACK\fR\fR
1845 .ad
1846 .RS 13n
1847 unrecoverable stack fault
1848 .RE
1849 
1850 .sp
1851 .ne 2
1852 .na
1853 \fB\fBFLTPAGE\fR\fR
1854 .ad
1855 .RS 13n
1856 recoverable page fault
1857 .RE
1858 
1859 .sp
1860 .LP
1861 When not traced, a fault normally results in the posting of a signal to the lwp
1862 that incurred the fault. If an lwp stops on a fault, the signal is posted to
1863 the lwp when execution is resumed unless the fault is cleared by \fBPCCFAULT\fR
1864 or by the \fBPRCFAULT\fR option of \fBPCRUN\fR. \fBFLTPAGE\fR is an exception;
1865 no signal is posted. The \fBpr_info\fR field in the \fBlwpstatus\fR structure
1866 identifies the signal to be sent and contains machine-specific information
1867 about the fault.
1868 .SS "PCCFAULT"
1869 .LP
1870 The current fault, if any, is cleared; the associated signal will not be sent
1871 to the specific or representative lwp.
1872 .SS "PCSENTRY PCSEXIT"
1873 .LP
1874 These control operations instruct the process's lwps to stop on entry to or
1875 exit from specified system calls. The set of system calls to be traced is
1876 defined via an operand \fBsysset_t\fR structure.
1877 .sp
1878 .LP
1879 When entry to a system call is being traced, an lwp stops after having begun
1880 the call to the system but before the system call arguments have been fetched
1881 from the lwp. When exit from a system call is being traced, an lwp stops on
1882 completion of the system call just prior to checking for signals and returning
1883 to user level. At this point, all return values have been stored into the lwp's
1884 registers.
1885 .sp
1886 .LP
1887 If an lwp is stopped on entry to a system call (\fBPR_SYSENTRY\fR) or when
1888 sleeping in an interruptible system call (\fBPR_ASLEEP\fR is set), it may be
1889 instructed to go directly to system call exit by specifying the \fBPRSABORT\fR
1890 flag in a \fBPCRUN\fR control message. Unless exit from the system call is
1891 being traced, the lwp returns to user level showing \fBEINTR\fR.
1892 .SS "PCWATCH"
1893 .LP
1894 Set or clear a watched area in the controlled process from a \fBprwatch\fR
1895 structure operand:
1896 .sp
1897 .in +2
1898 .nf
1899 typedef struct prwatch {
1900     uintptr_t pr_vaddr;  /* virtual address of watched area */
1901     size_t pr_size;      /* size of watched area in bytes */
1902     int pr_wflags;       /* watch type flags */
1903 } prwatch_t;
1904 .fi
1905 .in -2
1906 
1907 .sp
1908 .LP
1909 \fBpr_vaddr\fR specifies the virtual address of an area of memory to be watched
1910 in the controlled process. \fBpr_size\fR specifies the size of the area, in
1911 bytes. \fBpr_wflags\fR specifies the type of memory access to be monitored as a
1912 bit-mask of the following flags:
1913 .sp
1914 .ne 2
1915 .na
1916 \fB\fBWA_READ\fR\fR
1917 .ad
1918 .RS 16n
1919 read access
1920 .RE
1921 
1922 .sp
1923 .ne 2
1924 .na
1925 \fB\fBWA_WRITE\fR\fR
1926 .ad
1927 .RS 16n
1928 write access
1929 .RE
1930 
1931 .sp
1932 .ne 2
1933 .na
1934 \fB\fBWA_EXEC\fR\fR
1935 .ad
1936 .RS 16n
1937 execution access
1938 .RE
1939 
1940 .sp
1941 .ne 2
1942 .na
1943 \fB\fBWA_TRAPAFTER\fR\fR
1944 .ad
1945 .RS 16n
1946 trap after the instruction completes
1947 .RE
1948 
1949 .sp
1950 .LP
1951 If \fBpr_wflags\fR is non-empty, a watched area is established for the virtual
1952 address range specified by \fBpr_vaddr\fR and \fBpr_size\fR. If \fBpr_wflags\fR
1953 is empty, any previously-established watched area starting at the specified
1954 virtual address is cleared; \fBpr_size\fR is ignored.
1955 .sp
1956 .LP
1957 A watchpoint is triggered when an lwp in the traced process makes a memory
1958 reference that covers at least one byte of a watched area and the memory
1959 reference is as specified in \fBpr_wflags\fR. When an lwp triggers a
1960 watchpoint, it incurs a watchpoint trap. If \fBFLTWATCH\fR is being traced, the
1961 lwp stops; otherwise, it is sent a \fBSIGTRAP\fR signal; if \fBSIGTRAP\fR is
1962 being traced and is not blocked, the lwp stops.
1963 .sp
1964 .LP
1965 The watchpoint trap occurs before the instruction completes unless
1966 \fBWA_TRAPAFTER\fR was specified, in which case it occurs after the instruction
1967 completes. If it occurs before completion, the memory is not modified. If it
1968 occurs after completion, the memory is modified (if the access is a write
1969 access).
1970 .sp
1971 .LP
1972 Physical i/o is an exception for watchpoint traps. In this instance, there is
1973 no guarantee that memory before the watched area has already been modified (or
1974 in the case of \fBWA_TRAPAFTER\fR, that the memory following the watched area
1975 has not been modified) when the watchpoint trap occurs and the lwp stops.
1976 .sp
1977 .LP
1978 \fBpr_info\fR in the \fBlwpstatus\fR structure contains information pertinent
1979 to the watchpoint trap. In particular, the \fBsi_addr\fR field contains the
1980 virtual address of the memory reference that triggered the watchpoint, and the
1981 \fBsi_code\fR field contains one of \fBTRAP_RWATCH\fR, \fBTRAP_WWATCH\fR, or
1982 \fBTRAP_XWATCH\fR, indicating read, write, or execute access, respectively. The
1983 \fBsi_trapafter\fR field is zero unless \fBWA_TRAPAFTER\fR is in effect for
1984 this watched area; non-zero indicates that the current instruction is not the
1985 instruction that incurred the watchpoint trap. The \fBsi_pc\fR field contains
1986 the virtual address of the instruction that incurred the trap.
1987 .sp
1988 .LP
1989 A watchpoint trap may be triggered while executing a system call that makes
1990 reference to the traced process's memory. The lwp that is executing the system
1991 call incurs the watchpoint trap while still in the system call. If it stops as
1992 a result, the \fBlwpstatus\fR structure contains the system call number and its
1993 arguments. If the lwp does not stop, or if it is set running again without
1994 clearing the signal or fault, the system call fails with \fBEFAULT\fR. If
1995 \fBWA_TRAPAFTER\fR was specified, the memory reference will have completed and
1996 the memory will have been modified (if the access was a write access) when the
1997 watchpoint trap occurs.
1998 .sp
1999 .LP
2000 If more than one of \fBWA_READ\fR, \fBWA_WRITE\fR, and \fBWA_EXEC\fR is
2001 specified for a watched area, and a single instruction incurs more than one of
2002 the specified types, only one is reported when the watchpoint trap occurs. The
2003 precedence is \fBWA_EXEC\fR, \fBWA_READ\fR, \fBWA_WRITE\fR (\fBWA_EXEC\fR and
2004 \fBWA_READ\fR take precedence over \fBWA_WRITE\fR), unless \fBWA_TRAPAFTER\fR
2005 was specified, in which case it is \fBWA_WRITE\fR, \fBWA_READ\fR, \fBWA_EXEC\fR
2006 (\fBWA_WRITE\fR takes precedence).
2007 .sp
2008 .LP
2009 \fBPCWATCH\fR fails with \fBEINVAL\fR if an attempt is made to specify
2010 overlapping watched areas or if \fBpr_wflags\fR contains flags other than those
2011 specified above. It fails with \fBENOMEM\fR if an attempt is made to establish
2012 more watched areas than the system can support (the system can support
2013 thousands).
2014 .sp
2015 .LP
2016 The child of a \fBvfork\fR(2) borrows the parent's address space. When a
2017 \fBvfork\fR(2) is executed by a traced process, all watched areas established
2018 for the parent are suspended until the child terminates or performs an
2019 \fBexec\fR(2). Any watched areas established independently in the child are
2020 cancelled when the parent resumes after the child's termination or
2021 \fBexec\fR(2). \fBPCWATCH\fR fails with \fBEBUSY\fR if applied to the parent of
2022 a \fBvfork\fR(2) before the child has terminated or performed an \fBexec\fR(2).
2023 The \fBPR_VFORKP\fR flag is set in the \fBpstatus\fR structure for such a
2024 parent process.
2025 .sp
2026 .LP
2027 Certain accesses of the traced process's address space by the operating system
2028 are immune to watchpoints. The initial construction of a signal stack frame
2029 when a signal is delivered to an lwp will not trigger a watchpoint trap even if
2030 the new frame covers watched areas of the stack. Once the signal handler is
2031 entered, watchpoint traps occur normally. On SPARC based machines, register
2032 window overflow and underflow will not trigger watchpoint traps, even if the
2033 register window save areas cover watched areas of the stack.
2034 .sp
2035 .LP
2036 Watched areas are not inherited by child processes, even if the traced
2037 process's inherit-on-fork mode, \fBPR_FORK\fR, is set (see \fBPCSET\fR, below).
2038 All watched areas are cancelled when the traced process performs a successful
2039 \fBexec\fR(2).
2040 .SS "PCSET PCUNSET"
2041 .LP
2042 \fBPCSET\fR sets one or more modes of operation for the traced process.
2043 \fBPCUNSET\fR unsets these modes. The modes to be set or unset are specified by
2044 flags in an operand \fBlong\fR in the control message:
2045 .sp
2046 .ne 2
2047 .na
2048 \fB\fBPR_FORK\fR\fR
2049 .ad
2050 .RS 13n
2051 (inherit-on-fork): When set, the process's tracing flags and its
2052 inherit-on-fork mode are inherited by the child of a \fBfork\fR(2),
2053 \fBfork1\fR(2), or \fBvfork\fR(2). When unset, child processes start with all
2054 tracing flags cleared.
2055 .RE
2056 
2057 .sp
2058 .ne 2
2059 .na
2060 \fB\fBPR_RLC\fR\fR
2061 .ad
2062 .RS 13n
2063 (run-on-last-close): When set and the last writable \fB/proc\fR file descriptor
2064 referring to the traced process or any of its lwps is closed, all of the
2065 process's tracing flags and watched areas are cleared, any outstanding stop
2066 directives are canceled, and if any lwps are stopped on events of interest,
2067 they are set running as though \fBPCRUN\fR had been applied to them. When
2068 unset, the process's tracing flags and watched areas are retained and lwps are
2069 not set running on last close.
2070 .RE
2071 
2072 .sp
2073 .ne 2
2074 .na
2075 \fB\fBPR_KLC\fR\fR
2076 .ad
2077 .RS 13n
2078 (kill-on-last-close): When set and the last writable \fB/proc\fR file
2079 descriptor referring to the traced process or any of its lwps is closed, the
2080 process is terminated with \fBSIGKILL\fR.
2081 .RE
2082 
2083 .sp
2084 .ne 2
2085 .na
2086 \fB\fBPR_ASYNC\fR\fR
2087 .ad
2088 .RS 13n
2089 (asynchronous-stop): When set, a stop on an event of interest by one lwp does
2090 not directly affect any other lwp in the process. When unset and an lwp stops
2091 on an event of interest other than \fBPR_REQUESTED\fR, all other lwps in the
2092 process are directed to stop.
2093 .RE
2094 
2095 .sp
2096 .ne 2
2097 .na
2098 \fB\fBPR_MSACCT\fR\fR
2099 .ad
2100 .RS 13n
2101 (microstate accounting): Microstate accounting is now continuously enabled.
2102 This flag is deprecated and no longer has any effect upon microstate
2103 accounting. Applications may toggle this flag; however, microstate accounting
2104 will remain enabled regardless.
2105 .RE
2106 
2107 .sp
2108 .ne 2
2109 .na
2110 \fB\fBPR_MSFORK\fR\fR
2111 .ad
2112 .RS 13n
2113 (inherit microstate accounting): All processes now inherit microstate
2114 accounting, as it is continuously enabled. This flag has been deprecated and
2115 its use no longer has any effect upon the behavior of microstate accounting.
2116 .RE
2117 
2118 .sp
2119 .ne 2
2120 .na
2121 \fB\fBPR_BPTADJ\fR\fR
2122 .ad
2123 .RS 13n
2124 (breakpoint trap pc adjustment): On x86-based machines, a breakpoint trap
2125 leaves the program counter (the \fBEIP\fR) referring to the breakpointed
2126 instruction plus one byte. When \fBPR_BPTADJ\fR is set, the system will adjust
2127 the program counter back to the location of the breakpointed instruction when
2128 the lwp stops on a breakpoint. This flag has no effect on SPARC based machines,
2129 where breakpoint traps leave the program counter referring to the breakpointed
2130 instruction.
2131 .RE
2132 
2133 .sp
2134 .ne 2
2135 .na
2136 \fB\fBPR_PTRACE\fR\fR
2137 .ad
2138 .RS 13n
2139 (ptrace-compatibility): When set, a stop on an event of interest by the traced
2140 process is reported to the parent of the traced process by \fBwait\fR(3C),
2141 \fBSIGTRAP\fR is sent to the traced process when it executes a successful
2142 \fBexec\fR(2), setuid/setgid flags are not honored for execs performed by the
2143 traced process, any exec of an object file that the traced process cannot read
2144 fails, and the process dies when its parent dies. This mode is deprecated; it
2145 is provided only to allow \fBptrace\fR(3C) to be implemented as a library
2146 function using \fB/proc\fR.
2147 .RE
2148 
2149 .sp
2150 .LP
2151 It is an error (\fBEINVAL\fR) to specify flags other than those described above
2152 or to apply these operations to a system process. The current modes are
2153 reported in the \fBpr_flags\fR field of \fB/proc/\fR\fIpid\fR\fB/status\fR and
2154 \fB/proc/\fR\fIpid\fR\fB/lwp/\fR\fIlwp\fR\fB/lwpstatus\fR.
2155 .SS "PCSREG"
2156 .LP
2157 Set the general registers for the specific or representative lwp according to
2158 the operand \fBprgregset_t\fR structure.
2159 .sp
2160 .LP
2161 On SPARC based systems, only the condition-code bits of the processor-status
2162 register (R_PSR) of SPARC V8 (32-bit) processes can be modified by
2163 \fBPCSREG\fR. Other privileged registers cannot be modified at all.
2164 .sp
2165 .LP
2166 On x86-based systems, only certain bits of the flags register (EFL) can be
2167 modified by \fBPCSREG\fR: these include the condition codes, direction-bit, and
2168 overflow-bit.
2169 .sp
2170 .LP
2171 \fBPCSREG\fR fails with \fBEBUSY\fR if the lwp is not stopped on an event of
2172 interest.
2173 .SS "PCSVADDR"
2174 .LP
2175 Set the address at which execution will resume for the specific or
2176 representative lwp from the operand \fBlong\fR. On SPARC based systems, both
2177 %pc and %npc are set, with %npc set to the instruction following the virtual
2178 address. On x86-based systems, only %eip is set. \fBPCSVADDR\fR fails with
2179 \fBEBUSY\fR if the lwp is not stopped on an event of interest.
2180 .SS "PCSFPREG"
2181 .LP
2182 Set the floating-point registers for the specific or representative lwp
2183 according to the operand \fBprfpregset_t\fR structure. An error (\fBEINVAL\fR)
2184 is returned if the system does not support floating-point operations (no
2185 floating-point hardware and the system does not emulate floating-point machine
2186 instructions). \fBPCSFPREG\fR fails with \fBEBUSY\fR if the lwp is not stopped
2187 on an event of interest.
2188 .SS "PCSXREG"
2189 .LP
2190 Set the extra state registers for the specific or representative lwp according
2191 to the architecture-dependent operand \fBprxregset_t\fR structure. An error
2192 (\fBEINVAL\fR) is returned if the system does not support extra state
2193 registers. \fBPCSXREG\fR fails with \fBEBUSY\fR if the lwp is not stopped on an
2194 event of interest.
2195 .SS "PCSASRS"
2196 .LP
2197 Set the ancillary state registers for the specific or representative lwp
2198 according to the SPARC V9 platform-dependent operand \fBasrset_t\fR structure.
2199 An error (\fBEINVAL\fR) is returned if either the target process or the
2200 controlling process is not a 64-bit SPARC V9 process. Most of the ancillary
2201 state registers are privileged registers that cannot be modified. Only those
2202 that can be modified are set; all others are silently ignored. \fBPCSASRS\fR
2203 fails with \fBEBUSY\fR if the lwp is not stopped on an event of interest.
2204 .SS "PCAGENT"
2205 .LP
2206 Create an agent lwp in the controlled process with register values from the
2207 operand \fBprgregset_t\fR structure (see \fBPCSREG\fR, above). The agent lwp is
2208 created in the stopped state showing \fBPR_REQUESTED\fR and with its held
2209 signal set (the signal mask) having all signals except \fBSIGKILL\fR and
2210 \fBSIGSTOP\fR blocked.
2211 .sp
2212 .LP
2213 The \fBPCAGENT\fR operation fails with \fBEBUSY\fR unless the process is fully
2214 stopped via \fB/proc\fR, that is, unless all of the lwps in the process are
2215 stopped either on events of interest or on \fBPR_SUSPENDED\fR, or are stopped
2216 on \fBPR_JOBCONTROL\fR and have been directed to stop via \fBPCDSTOP\fR.  It
2217 fails with \fBEBUSY\fR if an agent lwp already exists. It fails with
2218 \fBENOMEM\fR if system resources for creating new lwps have been exhausted.
2219 .sp
2220 .LP
2221 Any \fBPCRUN\fR operation applied to the process control file or to the control
2222 file of an lwp other than the agent lwp fails with \fBEBUSY\fR as long as the
2223 agent lwp exists. The agent lwp must be caused to terminate by executing the
2224 \fBSYS_lwp_exit\fR system call trap before the process can be restarted.
2225 .sp
2226 .LP
2227 Once the agent lwp is created, its lwp-ID can be found by reading the process
2228 status file. To facilitate opening the agent lwp's control and status files,
2229 the directory name \fB/propc/\fR\fIpid\fR\fB/lwp/agent\fR is accepted for
2230 lookup operations as an invisible alias for
2231 \fB/proc/\fR\fIpid\fR\fB/lwp/\fR\fIlwpid,\fR \fIlwpid\fR being the lwp-ID of
2232 the agent lwp (invisible in the sense that the name ``agent'' does not appear
2233 in a directory listing of \fB/proc/\fR\fIpid\fR\fB/lwp\fR obtained from
2234 \fBls\fR(1), \fBgetdents\fR(2), or \fBreaddir\fR(3C)).
2235 .sp
2236 .LP
2237 The purpose of the agent lwp is to perform operations in the controlled process
2238 on behalf of the controlling process: to gather information not directly
2239 available via \fB/proc\fR files, or in general to make the process change state
2240 in ways not directly available via \fB/proc\fR control operations. To make use
2241 of an agent lwp, the controlling process must be capable of making it execute
2242 system calls (specifically, the \fBSYS_lwp_exit\fR system call trap). The
2243 register values given to the agent lwp on creation are typically the registers
2244 of the representative lwp, so that the agent lwp can use its stack.
2245 .sp
2246 .LP
2247 If the controlling process neglects to force the agent lwp to execute the
2248 \fBSYS_lwp_exit\fR system call (due to either logic error or fatal failure on
2249 the part of the controlling process), the agent lwp will remain in the target
2250 process.  For purposes of being able to debug these otherwise rogue agents,
2251 information as to the creator of the agent lwp is reflected in that lwp's
2252 \fBspymaster\fR file in \fB/proc\fR. Should the target process generate a core
2253 dump with the agent lwp in place, this information will be available via the
2254 \fBNT_SPYMASTER\fR note in the core file (see \fBcore\fR(4)).
2255 .sp
2256 .LP
2257 The agent lwp is not allowed to execute any variation of the \fBSYS_fork\fR or
2258 \fBSYS_exec\fR system call traps. Attempts to do so yield \fBENOTSUP\fR to the
2259 agent lwp.
2260 .sp
2261 .LP
2262 Symbolic constants for system call trap numbers like \fBSYS_lwp_exit\fR and
2263 \fBSYS_lwp_create\fR can be found in the header file <\fBsys/syscall.h\fR>.
2264 .SS "PCREAD PCWRITE"
2265 .LP
2266 Read or write the target process's address space via a \fBpriovec\fR structure
2267 operand:
2268 .sp
2269 .in +2
2270 .nf
2271 typedef struct priovec {
2272     void *pio_base;      /* buffer in controlling process */
2273     size_t pio_len;      /* size of read/write request in bytes */
2274     off_t pio_offset;    /* virtual address in target process */
2275 } priovec_t;
2276 .fi
2277 .in -2
2278 
2279 .sp
2280 .LP
2281 These operations have the same effect as \fBpread\fR(2) and \fBpwrite\fR(2),
2282 respectively, of the target process's address space file. The difference is
2283 that more than one \fBPCREAD\fR or \fBPCWRITE\fR control operation can be
2284 written to the control file at once, and they can be interspersed with other
2285 control operations in a single write to the control file. This is useful, for
2286 example, when planting many breakpoint instructions in the process's address
2287 space, or when stepping over a breakpointed instruction. Unlike \fBpread\fR(2)
2288 and \fBpwrite\fR(2), no provision is made for partial reads or writes; if the
2289 operation cannot be performed completely, it fails with \fBEIO\fR.
2290 .SS "PCNICE"
2291 .LP
2292 The traced process's \fBnice\fR(2) value is incremented by the amount in the
2293 operand \fBlong\fR. Only a process with the {\fBPRIV_PROC_PRIOCNTL\fR}
2294 privilege asserted in its effective set can better a process's priority in this
2295 way, but any user may lower the priority. This operation is not meaningful for
2296 all scheduling classes.
2297 .SS "PCSCRED"
2298 .LP
2299 Set the target process credentials to the values contained in the
2300 \fBprcred_t\fR structure operand (see \fB/proc/\fR\fIpid\fR\fB/cred\fR). The
2301 effective, real, and saved user-IDs and group-IDs of the target process are
2302 set. The target process's supplementary groups are not changed; the
2303 \fBpr_ngroups\fR and \fBpr_groups\fR members of the structure operand are
2304 ignored. Only the privileged processes can perform this operation; for all
2305 others it fails with \fBEPERM\fR.
2306 .SS "PCSCREDX"
2307 .LP
2308 Operates like \fBPCSCRED\fR but also sets the supplementary groups; the length
2309 of the data written with this control operation should be "sizeof
2310 (\fBprcred_t\fR) + sizeof (\fBgid_t)\fR * (#groups - 1)".
2311 .SS "PCSPRIV"
2312 .LP
2313 Set the target process privilege to the values contained in the \fBprpriv_t\fR
2314 operand (see \fB/proc/pid/priv\fR). The effective, permitted, inheritable, and
2315 limit sets are all changed. Privilege flags can also be set. The process is
2316 made privilege aware unless it can relinquish privilege awareness. See
2317 \fBprivileges\fR(5).
2318 .sp
2319 .LP
2320 The limit set of the target process cannot be grown. The other privilege sets
2321 must be subsets of the intersection of the effective set of the calling process
2322 with the new limit set of the target process or subsets of the original values
2323 of the sets in the target process.
2324 .sp
2325 .LP
2326 If any of the above restrictions are not met, \fBEPERM\fR is returned. If the
2327 structure written is improperly formatted, \fBEINVAL\fR is returned.
2328 .SH PROGRAMMING NOTES
2329 .LP
2330 For security reasons, except for the \fBpsinfo\fR, \fBusage\fR, \fBlpsinfo\fR,
2331 \fBlusage\fR, \fBlwpsinfo\fR, and \fBlwpusage\fR files, which are
2332 world-readable, and except for privileged processes, an open of a \fB/proc\fR
2333 file fails unless both the user-ID and group-ID of the caller match those of
2334 the traced process and the process's object file is readable by the caller. The
2335 effective set of the caller is a superset of both the inheritable and the
2336 permitted set of the target process. The limit set of the caller is a superset
2337 of the limit set of the target process. Except for the world-readable files
2338 just mentioned, files corresponding to setuid and setgid processes can be
2339 opened only by the appropriately privileged process.
2340 .sp
2341 .LP
2342 A process that is missing the basic privilege {\fBPRIV_PROC_INFO\fR} cannot see
2343 any processes under \fB/proc\fR that it cannot send a signal to.
2344 .sp
2345 .LP
2346 A process that has {\fBPRIV_PROC_OWNER\fR} asserted in its effective set can
2347 open any file for reading. To manipulate or control a process, the controlling
2348 process must have at least as many privileges in its effective set as the
2349 target process has in its effective, inheritable, and permitted sets. The limit
2350 set of the controlling process must be a superset of the limit set of the
2351 target process. Additional restrictions apply if any of the uids of the target
2352 process are 0. See \fBprivileges\fR(5).
2353 .sp
2354 .LP
2355 Even if held by a privileged process, an open process or lwp file descriptor
2356 (other than file descriptors for the world-readable files) becomes invalid if
2357 the traced process performs an \fBexec\fR(2) of a setuid/setgid object file or
2358 an object file that the traced process cannot read. Any operation performed on
2359 an invalid file descriptor, except \fBclose\fR(2), fails with \fBEAGAIN\fR. In
2360 this situation, if any tracing flags are set and the process or any lwp file
2361 descriptor is open for writing, the process will have been directed to stop and
2362 its run-on-last-close flag will have been set (see \fBPCSET\fR). This enables a
2363 controlling process (if it has permission) to reopen the \fB/proc\fR files to
2364 get new valid file descriptors, close the invalid file descriptors, unset the
2365 run-on-last-close flag (if desired), and proceed. Just closing the invalid file
2366 descriptors causes the traced process to resume execution with all tracing
2367 flags cleared. Any process not currently open for writing via \fB/proc\fR, but
2368 that has left-over tracing flags from a previous open, and that executes a
2369 setuid/setgid or unreadable object file, will not be stopped but will have all
2370 its tracing flags cleared.
2371 .sp
2372 .LP
2373 To wait for one or more of a set of processes or lwps to stop or terminate,
2374 \fB/proc\fR file descriptors (other than those obtained by opening the
2375 \fBcwd\fR or \fBroot\fR directories or by opening files in the \fBfd\fR or
2376 \fBobject\fR directories) can be used in a \fBpoll\fR(2) system call. When
2377 requested and returned, either of the polling events \fBPOLLPRI\fR or
2378 \fBPOLLWRNORM\fR indicates that the process or lwp stopped on an event of
2379 interest. Although they cannot be requested, the polling events \fBPOLLHUP\fR,
2380 \fBPOLLERR\fR, and \fBPOLLNVAL\fR may be returned. \fBPOLLHUP\fR indicates that
2381 the process or lwp has terminated. \fBPOLLERR\fR indicates that the file
2382 descriptor has become invalid. \fBPOLLNVAL\fR is returned immediately if
2383 \fBPOLLPRI\fR or \fBPOLLWRNORM\fR is requested on a file descriptor referring
2384 to a system process (see \fBPCSTOP\fR). The requested events may be empty to
2385 wait simply for termination.
2386 .SH FILES
2387 .ne 2
2388 .na
2389 \fB\fB/proc\fR\fR
2390 .ad
2391 .sp .6
2392 .RS 4n
2393 directory (list of processes)
2394 .RE
2395 
2396 .sp
2397 .ne 2
2398 .na
2399 \fB\fB/proc/\fIpid\fR\fR\fR
2400 .ad
2401 .sp .6
2402 .RS 4n
2403 specific process directory
2404 .RE
2405 
2406 .sp
2407 .ne 2
2408 .na
2409 \fB\fB/proc/self\fR\fR
2410 .ad
2411 .sp .6
2412 .RS 4n
2413 alias for a process's own directory
2414 .RE
2415 
2416 .sp
2417 .ne 2
2418 .na
2419 \fB\fB/proc/\fIpid\fR/as\fR\fR
2420 .ad
2421 .sp .6
2422 .RS 4n
2423 address space file
2424 .RE
2425 
2426 .sp
2427 .ne 2
2428 .na
2429 \fB\fB/proc/\fIpid\fR/ctl\fR\fR
2430 .ad
2431 .sp .6
2432 .RS 4n
2433 process control file
2434 .RE
2435 
2436 .sp
2437 .ne 2
2438 .na
2439 \fB\fB/proc/\fIpid\fR/status\fR\fR
2440 .ad
2441 .sp .6
2442 .RS 4n
2443 process status
2444 .RE
2445 
2446 .sp
2447 .ne 2
2448 .na
2449 \fB\fB/proc/\fIpid\fR/lstatus\fR\fR
2450 .ad
2451 .sp .6
2452 .RS 4n
2453 array of lwp status structs
2454 .RE
2455 
2456 .sp
2457 .ne 2
2458 .na
2459 \fB\fB/proc/\fIpid\fR/psinfo\fR\fR
2460 .ad
2461 .sp .6
2462 .RS 4n
2463 process \fBps\fR(1) info
2464 .RE
2465 
2466 .sp
2467 .ne 2
2468 .na
2469 \fB\fB/proc/\fIpid\fR/lpsinfo\fR\fR
2470 .ad
2471 .sp .6
2472 .RS 4n
2473 array of lwp \fBps\fR(1) info structs
2474 .RE
2475 
2476 .sp
2477 .ne 2
2478 .na
2479 \fB\fB/proc/\fIpid\fR/map\fR\fR
2480 .ad
2481 .sp .6
2482 .RS 4n
2483 address space map
2484 .RE
2485 
2486 .sp
2487 .ne 2
2488 .na
2489 \fB\fB/proc/\fIpid\fR/xmap\fR\fR
2490 .ad
2491 .sp .6
2492 .RS 4n
2493 extended address space map
2494 .RE
2495 
2496 .sp
2497 .ne 2
2498 .na
2499 \fB\fB/proc/\fIpid\fR/rmap\fR\fR
2500 .ad
2501 .sp .6
2502 .RS 4n
2503 reserved address map
2504 .RE
2505 
2506 .sp
2507 .ne 2
2508 .na
2509 \fB\fB/proc/\fIpid\fR/cred\fR\fR
2510 .ad
2511 .sp .6
2512 .RS 4n
2513 process credentials
2514 .RE
2515 
2516 .sp
2517 .ne 2
2518 .na
2519 \fB\fB/proc/\fIpid\fR/priv\fR\fR
2520 .ad
2521 .sp .6
2522 .RS 4n
2523 process privileges
2524 .RE
2525 
2526 .sp
2527 .ne 2
2528 .na
2529 \fB\fB/proc/\fIpid\fR/sigact\fR\fR
2530 .ad
2531 .sp .6
2532 .RS 4n
2533 process signal actions
2534 .RE
2535 
2536 .sp
2537 .ne 2
2538 .na
2539 \fB\fB/proc/\fIpid\fR/auxv\fR\fR
2540 .ad
2541 .sp .6
2542 .RS 4n
2543 process aux vector
2544 .RE
2545 
2546 .sp
2547 .ne 2
2548 .na
2549 \fB\fB/proc/\fIpid\fR/ldt\fR\fR
2550 .ad
2551 .sp .6
2552 .RS 4n
2553 process \fBLDT\fR (x86 only)
2554 .RE
2555 
2556 .sp
2557 .ne 2
2558 .na
2559 \fB\fB/proc/\fIpid\fR/usage\fR\fR
2560 .ad
2561 .sp .6
2562 .RS 4n
2563 process usage
2564 .RE
2565 
2566 .sp
2567 .ne 2
2568 .na
2569 \fB\fB/proc/\fIpid\fR/lusage\fR\fR
2570 .ad
2571 .sp .6
2572 .RS 4n
2573 array of lwp usage structs
2574 .RE
2575 
2576 .sp
2577 .ne 2
2578 .na
2579 \fB\fB/proc/\fIpid\fR/path\fR\fR
2580 .ad
2581 .sp .6
2582 .RS 4n
2583 symbolic links to process open files
2584 .RE
2585 
2586 .sp
2587 .ne 2
2588 .na
2589 \fB\fB/proc/\fIpid\fR/pagedata\fR\fR
2590 .ad
2591 .sp .6
2592 .RS 4n
2593 process page data
2594 .RE
2595 
2596 .sp
2597 .ne 2
2598 .na
2599 \fB\fB/proc/\fIpid\fR/watch\fR\fR
2600 .ad
2601 .sp .6
2602 .RS 4n
2603 active watchpoints
2604 .RE
2605 
2606 .sp
2607 .ne 2
2608 .na
2609 \fB\fB/proc/\fIpid\fR/cwd\fR\fR
2610 .ad
2611 .sp .6
2612 .RS 4n
2613 alias for the current working directory
2614 .RE
2615 
2616 .sp
2617 .ne 2
2618 .na
2619 \fB\fB/proc/\fIpid\fR/root\fR\fR
2620 .ad
2621 .sp .6
2622 .RS 4n
2623 alias for the root directory
2624 .RE
2625 
2626 .sp
2627 .ne 2
2628 .na
2629 \fB\fB/proc/\fIpid\fR/fd\fR\fR
2630 .ad
2631 .sp .6
2632 .RS 4n
2633 directory (list of open files)
2634 .RE
2635 
2636 .sp
2637 .ne 2
2638 .na
2639 \fB\fB/proc/\fIpid\fR/fd/*\fR\fR
2640 .ad
2641 .sp .6
2642 .RS 4n
2643 aliases for process's open files
2644 .RE
2645 
2646 .sp
2647 .ne 2
2648 .na
2649 \fB\fB/proc/\fIpid\fR/object\fR\fR
2650 .ad
2651 .sp .6
2652 .RS 4n
2653 directory (list of mapped files)
2654 .RE
2655 
2656 .sp
2657 .ne 2
2658 .na
2659 \fB\fB/proc/\fIpid\fR/object/a.out\fR\fR
2660 .ad
2661 .sp .6
2662 .RS 4n
2663 alias for process's executable file
2664 .RE
2665 
2666 .sp
2667 .ne 2
2668 .na
2669 \fB\fB/proc/\fIpid\fR/object/*\fR\fR
2670 .ad
2671 .sp .6
2672 .RS 4n
2673 aliases for other mapped files
2674 .RE
2675 
2676 .sp
2677 .ne 2
2678 .na
2679 \fB\fB/proc/\fIpid\fR/lwp\fR\fR
2680 .ad
2681 .sp .6
2682 .RS 4n
2683 directory (list of lwps)
2684 .RE
2685 
2686 .sp
2687 .ne 2
2688 .na
2689 \fB\fB/proc/\fIpid\fR/lwp/\fIlwpid\fR\fR\fR
2690 .ad
2691 .sp .6
2692 .RS 4n
2693 specific lwp directory
2694 .RE
2695 
2696 .sp
2697 .ne 2
2698 .na
2699 \fB\fB/proc/\fIpid\fR/lwp/agent\fR\fR
2700 .ad
2701 .sp .6
2702 .RS 4n
2703 alias for the agent lwp directory
2704 .RE
2705 
2706 .sp
2707 .ne 2
2708 .na
2709 \fB\fB/proc/\fIpid\fR/lwp/\fIlwpid\fR/lwpctl\fR\fR
2710 .ad
2711 .sp .6
2712 .RS 4n
2713 lwp control file
2714 .RE
2715 
2716 .sp
2717 .ne 2
2718 .na
2719 \fB\fB/proc/\fIpid\fR/lwp/\fIlwpid\fR/lwpstatus\fR\fR
2720 .ad
2721 .sp .6
2722 .RS 4n
2723 lwp status
2724 .RE
2725 
2726 .sp
2727 .ne 2
2728 .na
2729 \fB\fB/proc/\fIpid\fR/lwp/\fIlwpid\fR/lwpsinfo\fR\fR
2730 .ad
2731 .sp .6
2732 .RS 4n
2733 lwp \fBps\fR(1) info
2734 .RE
2735 
2736 .sp
2737 .ne 2
2738 .na
2739 \fB\fB/proc/\fIpid\fR/lwp/\fIlwpid\fR/lwpusage\fR\fR
2740 .ad
2741 .sp .6
2742 .RS 4n
2743 lwp usage
2744 .RE
2745 
2746 .sp
2747 .ne 2
2748 .na
2749 \fB\fB/proc/\fIpid\fR/lwp/\fIlwpid\fR/gwindows\fR\fR
2750 .ad
2751 .sp .6
2752 .RS 4n
2753 register windows (SPARC only)
2754 .RE
2755 
2756 .sp
2757 .ne 2
2758 .na
2759 \fB\fB/proc/\fIpid\fR/lwp/\fIlwpid\fR/xregs\fR\fR
2760 .ad
2761 .sp .6
2762 .RS 4n
2763 extra state registers
2764 .RE
2765 
2766 .sp
2767 .ne 2
2768 .na
2769 \fB\fB/proc/\fIpid\fR/lwp/\fIlwpid\fR/asrs\fR\fR
2770 .ad
2771 .sp .6
2772 .RS 4n
2773 ancillary state registers (SPARC V9 only)
2774 .RE
2775 
2776 .sp
2777 .ne 2
2778 .na
2779 \fB\fB/proc/\fIpid\fR/lwp/\fIlwpid\fR/spymaster\fR\fR
2780 .ad
2781 .sp .6
2782 .RS 4n
2783 For an agent LWP, the controlling process
2784 .RE
2785 
2786 .SH SEE ALSO
2787 .LP
2788 \fBls\fR(1), \fBps\fR(1), \fBchroot\fR(1M), \fBalarm\fR(2), \fBbrk\fR(2),
2789 \fBchdir\fR(2), \fBchroot\fR(2), \fBclose\fR(2), \fBcreat\fR(2), \fBdup\fR(2),
2790 \fBexec\fR(2), \fBfcntl\fR(2), \fBfork\fR(2), \fBfork1\fR(2), \fBfstat\fR(2),
2791 \fBgetdents\fR(2), \fBgetustack\fR(2), \fBkill\fR(2), \fBlseek\fR(2),
2792 \fBmmap\fR(2), \fBnice\fR(2), \fBopen\fR(2), \fBpoll\fR(2), \fBpread\fR(2),
2793 \fBptrace\fR(3C), \fBpwrite\fR(2), \fBread\fR(2), \fBreadlink\fR(2),
2794 \fBreadv\fR(2), \fBshmget\fR(2), \fBsigaction\fR(2), \fBsigaltstack\fR(2),
2795 \fBvfork\fR(2), \fBwrite\fR(2), \fBwritev\fR(2), \fB_stack_grow\fR(3C),
2796 \fBreaddir\fR(3C), \fBpthread_create\fR(3C), \fBpthread_join\fR(3C),
2797 \fBsiginfo.h\fR(3HEAD), \fBsignal.h\fR(3HEAD), \fBthr_create\fR(3C),
2798 \fBthr_join\fR(3C), \fBtypes32.h\fR(3HEAD), \fBucontext.h\fR(3HEAD),
2799 \fBwait\fR(3C), \fBcontract\fR(4), \fBcore\fR(4), \fBprocess\fR(4),
2800 \fBlfcompile\fR(5), \fBprivileges\fR(5), \fBsecurity-flags\fR(5)
2801 .SH DIAGNOSTICS
2802 .LP
2803 Errors that can occur in addition to the errors normally associated with file
2804 system access:
2805 .sp
2806 .ne 2
2807 .na
2808 \fB\fBE2BIG\fR\fR
2809 .ad
2810 .RS 13n
2811 Data to be returned in a \fBread\fR(2) of the page data file exceeds the size
2812 of the read buffer provided by the caller.
2813 .RE
2814 
2815 .sp
2816 .ne 2
2817 .na
2818 \fB\fBEACCES\fR\fR
2819 .ad
2820 .RS 13n
2821 An attempt was made to examine a process that ran under a different uid than
2822 the controlling process and {\fBPRIV_PROC_OWNER\fR} was not asserted in the
2823 effective set.
2824 .RE
2825 
2826 .sp
2827 .ne 2
2828 .na
2829 \fB\fBEAGAIN\fR\fR
2830 .ad
2831 .RS 13n
2832 The traced process has performed an \fBexec\fR(2) of a setuid/setgid object
2833 file or of an object file that it cannot read; all further operations on the
2834 process or lwp file descriptor (except \fBclose\fR(2)) elicit this error.
2835 .RE
2836 
2837 .sp
2838 .ne 2
2839 .na
2840 \fB\fBEBUSY\fR\fR
2841 .ad
2842 .RS 13n
2843 \fBPCSTOP\fR, \fBPCDSTOP\fR, \fBPCWSTOP\fR, or \fBPCTWSTOP\fR was applied to a
2844 system process; an exclusive \fBopen\fR(2) was attempted on a \fB/proc\fR file
2845 for a process already open for writing; \fBPCRUN\fR, \fBPCSREG\fR,
2846 \fBPCSVADDR\fR, \fBPCSFPREG\fR, or \fBPCSXREG\fR was applied to a process or
2847 lwp not stopped on an event of interest; an attempt was made to mount
2848 \fB/proc\fR when it was already mounted; \fBPCAGENT\fR was applied to a process
2849 that was not fully stopped or that already had an agent lwp.
2850 .RE
2851 
2852 .sp
2853 .ne 2
2854 .na
2855 \fB\fBEINVAL\fR\fR
2856 .ad
2857 .RS 13n
2858 In general, this means that some invalid argument was supplied to a system
2859 call. A non-exhaustive list of conditions eliciting this error includes: a
2860 control message operation code is undefined; an out-of-range signal number was
2861 specified with \fBPCSSIG\fR, \fBPCKILL\fR, or \fBPCUNKILL\fR; \fBSIGKILL\fR was
2862 specified with \fBPCUNKILL\fR; \fBPCSFPREG\fR was applied on a system that does
2863 not support floating-point operations; \fBPCSXREG\fR was applied on a system
2864 that does not support extra state registers.
2865 .RE
2866 
2867 .sp
2868 .ne 2
2869 .na
2870 \fB\fBEINTR\fR\fR
2871 .ad
2872 .RS 13n
2873 A signal was received by the controlling process while waiting for the traced
2874 process or lwp to stop via \fBPCSTOP\fR, \fBPCWSTOP\fR, or \fBPCTWSTOP\fR.
2875 .RE
2876 
2877 .sp
2878 .ne 2
2879 .na
2880 \fB\fBEIO\fR\fR
2881 .ad
2882 .RS 13n
2883 A \fBwrite\fR(2) was attempted at an illegal address in the traced process.
2884 .RE
2885 
2886 .sp
2887 .ne 2
2888 .na
2889 \fB\fBENOENT\fR\fR
2890 .ad
2891 .RS 13n
2892 The traced process or lwp has terminated after being opened. The basic
2893 privilege {\fBPRIV_PROC_INFO\fR} is not asserted in the effective set of the
2894 calling process and the calling process cannot send a signal to the target
2895 process.
2896 .RE
2897 
2898 .sp
2899 .ne 2
2900 .na
2901 \fB\fBENOMEM\fR\fR
2902 .ad
2903 .RS 13n
2904 The system-imposed limit on the number of page data file descriptors was
2905 reached on an open of \fB/proc/\fR\fIpid\fR\fB/pagedata\fR; an attempt was made
2906 with \fBPCWATCH\fR to establish more watched areas than the system can support;
2907 the \fBPCAGENT\fR operation was issued when the system was out of resources for
2908 creating lwps.
2909 .RE
2910 
2911 .sp
2912 .ne 2
2913 .na
2914 \fB\fBENOSYS\fR\fR
2915 .ad
2916 .RS 13n
2917 An attempt was made to perform an unsupported operation (such as
2918 \fBcreat\fR(2), \fBlink\fR(2), or \fBunlink\fR(2)) on an entry in \fB/proc\fR.
2919 .RE
2920 
2921 .sp
2922 .ne 2
2923 .na
2924 \fB\fBEOVERFLOW\fR\fR
2925 .ad
2926 .RS 13n
2927 A 32-bit controlling process attempted to read or write the \fBas\fR file or
2928 attempted to read the \fBmap\fR, \fBrmap\fR, or \fBpagedata\fR file of a 64-bit
2929 target process. A 32-bit controlling process attempted to apply one of the
2930 control operations \fBPCSREG\fR, \fBPCSXREG\fR, \fBPCSVADDR\fR, \fBPCWATCH\fR,
2931 \fBPCAGENT\fR, \fBPCREAD\fR, \fBPCWRITE\fR to a 64-bit target process.
2932 .RE
2933 
2934 .sp
2935 .ne 2
2936 .na
2937 \fB\fBEPERM\fR\fR
2938 .ad
2939 .RS 13n
2940 The process that issued the \fBPCSCRED\fR or \fBPCSCREDX\fR operation did not
2941 have the {\fBPRIV_PROC_SETID\fR} privilege asserted in its effective set, or
2942 the process that issued the \fBPCNICE\fR operation did not have the
2943 {\fBPRIV_PROC_PRIOCNTL\fR} in its effective set.
2944 .sp
2945 An attempt was made to control a process of which the E, P, and I privilege
2946 sets were not a subset of the effective set of the controlling process or the
2947 limit set of the controlling process is not a superset of limit set of the
2948 controlled process.
2949 .sp
2950 Any of the uids of the target process are 0 or an attempt was made to change
2951 any of the uids to 0 using PCSCRED and the security policy imposed additional
2952 restrictions. See \fBprivileges\fR(5).
2953 .RE
2954 
2955 .SH NOTES
2956 .LP
2957 Descriptions of structures in this document include only interesting structure
2958 elements, not filler and padding fields, and may show elements out of order for
2959 descriptive clarity. The actual structure definitions are contained in
2960 \fB<procfs.h>\fR\&.
2961 .SH BUGS
2962 .LP
2963 Because the old \fBioctl\fR(2)-based version of \fB/proc\fR is currently
2964 supported for binary compatibility with old applications, the top-level
2965 directory for a process, \fB/proc/\fR\fIpid\fR, is not world-readable, but it
2966 is world-searchable. Thus, anyone can open \fB/proc/\fR\fIpid\fR\fB/psinfo\fR
2967 even though \fBls\fR(1) applied to \fB/proc/\fR\fIpid\fR will fail for anyone
2968 but the owner or an appropriately privileged process. Support for the old
2969 \fBioctl\fR(2)-based version of \fB/proc\fR will be dropped in a future
2970 release, at which time the top-level directory for a process will be made
2971 world-readable.
2972 .sp
2973 .LP
2974 On SPARC based machines, the types \fBgregset_t\fR and \fBfpregset_t\fR defined
2975 in <\fBsys/regset.h\fR> are similar to but not the same as the types
2976 \fBprgregset_t\fR and \fBprfpregset_t\fR defined in <\fBprocfs.h\fR>.