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  48 .TH CRONTAB 1 "Oct 22, 2019"
  49 .SH NAME
  50 crontab \- user crontab file
  51 .SH SYNOPSIS
  52 .nf
  53 \fB/usr/bin/crontab\fR [\fIfilename\fR]
  54 .fi
  55 
  56 .LP
  57 .nf
  58 \fB/usr/bin/crontab\fR \fB-e\fR [\fIusername\fR]
  59 .fi
  60 
  61 .LP
  62 .nf
  63 \fB/usr/bin/crontab\fR \fB-l\fR [\fIusername\fR]
  64 .fi
  65 
  66 .LP
  67 .nf
  68 \fB/usr/bin/crontab\fR \fB-r\fR [\fIusername\fR]
  69 .fi
  70 
  71 .LP
  72 .nf
  73 \fB/usr/xpg4/bin/crontab\fR [\fIfilename\fR]
  74 .fi
  75 
  76 .LP
  77 .nf
  78 \fB/usr/xpg4/bin/crontab\fR \fB-e\fR [\fIusername\fR]
  79 .fi
  80 
  81 .LP
  82 .nf
  83 \fB/usr/xpg4/bin/crontab\fR \fB-l\fR [\fIusername\fR]
  84 .fi
  85 
  86 .LP
  87 .nf
  88 \fB/usr/xpg4/bin/crontab\fR \fB-r\fR [\fIusername\fR]
  89 .fi
  90 
  91 .LP
  92 .nf
  93 \fB/usr/xpg6/bin/crontab\fR [\fIfilename\fR]
  94 .fi
  95 
  96 .LP
  97 .nf
  98 \fB/usr/xpg6/bin/crontab\fR \fB-e\fR [\fIusername\fR]
  99 .fi
 100 
 101 .LP
 102 .nf
 103 \fB/usr/xpg6/bin/crontab\fR \fB-l\fR [\fIusername\fR]
 104 .fi
 105 
 106 .LP
 107 .nf
 108 \fB/usr/xpg6/bin/crontab\fR \fB-r\fR [\fIusername\fR]
 109 .fi
 110 
 111 .SH DESCRIPTION
 112 The \fBcrontab\fR utility manages a user's access with \fBcron\fR (see
 113 \fBcron\fR(1M)) by copying, creating, listing, and removing \fBcrontab\fR
 114 files. If invoked without options, \fBcrontab\fR copies the specified file, or
 115 the standard input if no file is specified, into a directory that holds all
 116 users' crontabs.
 117 .sp
 118 .LP
 119 If \fBcrontab\fR is invoked with \fIfilename\fR, this overwrites an existing
 120 \fBcrontab\fR entry for the user that invokes it.
 121 .SS "\fBcrontab\fR Access Control"
 122 Users: Access to \fBcrontab\fR is allowed:
 123 .RS +4
 124 .TP
 125 .ie t \(bu
 126 .el o
 127 if the user's name appears in \fB/etc/cron.d/cron.allow\fR.
 128 .RE
 129 .RS +4
 130 .TP
 131 .ie t \(bu
 132 .el o
 133 if \fB/etc/cron.d/cron.allow\fR does not exist and the user's name is not in
 134 \fB/etc/cron.d/cron.deny\fR.
 135 .RE
 136 .sp
 137 .LP
 138 Users: Access to \fBcrontab\fR is denied:
 139 .RS +4
 140 .TP
 141 .ie t \(bu
 142 .el o
 143 if \fB/etc/cron.d/cron.allow\fR exists and the user's name is not in it.
 144 .RE
 145 .RS +4
 146 .TP
 147 .ie t \(bu
 148 .el o
 149 if \fB/etc/cron.d/cron.allow\fR does not exist and user's name is in
 150 \fB/etc/cron.d/cron.deny\fR.
 151 .RE
 152 .RS +4
 153 .TP
 154 .ie t \(bu
 155 .el o
 156 if neither file exists, only a user with the \fBsolaris.jobs.user\fR
 157 authorization is allowed to submit a job.
 158 .RE
 159 .RS +4
 160 .TP
 161 .ie t \(bu
 162 .el o
 163 if Auditing is enabled, the user's shell is not audited and the user is
 164 not the \fBcrontab\fR owner. This can occur if the user logs in by way of a
 165 program, such as some versions of \fBSSH\fR, which does not set audit
 166 parameters.
 167 .RE
 168 .sp
 169 .LP
 170 The rules for \fBallow\fR and \fBdeny\fR apply to \fBroot\fR only if the
 171 \fBallow\fR/\fBdeny\fR files exist.
 172 .sp
 173 .LP
 174 The \fBallow\fR/\fBdeny\fR files consist of one user name per line.
 175 .SS "\fBcrontab\fR Entry Format"
 176 A \fBcrontab\fR file consists of lines of six fields each. The fields are
 177 separated by spaces or tabs. The first five are integer patterns that specify
 178 the following:
 179 .sp
 180 .in +2
 181 .nf
 182 minute (0\(mi59),
 183 hour (0\(mi23),
 184 day of the month (1\(mi31),
 185 month of the year (1\(mi12),
 186 day of the week (0\(mi6 with 0=Sunday).
 187 .fi
 188 .in -2
 189 .sp
 190 
 191 .sp
 192 .LP
 193 Each of these patterns can be either an asterisk (meaning all legal values) or
 194 a list of elements separated by commas. An element is either a number or two
 195 numbers separated by a hyphen (meaning an inclusive range).
 196 .LP
 197 A range or asterisk can optionally be followed by a step value as
 198 \fI/<number>\fR. For example, \fI2\(mi59/3\fR can be used in the minutes field
 199 to specify every three minutes starting at 2 past the hour, or \fI*/2\fR in
 200 the hours field means every two hours.
 201 .LP
 202 Time specified here is interpreted in the currently active timezone. At the top
 203 of the crontab file this is the timezone which is set system-wide in
 204 /etc/default/init. A user can add a line such as:
 205 .sp
 206 .in +2
 207 .nf
 208 TZ=\fItimezone\fR
 209 .fi
 210 .in -2
 211 .sp
 212 
 213 .sp
 214 .LP
 215 \&...and all subsequent entries will be interpreted using that timezone, until
 216 a new \fBTZ=\fR\fItimezone\fR line is encountered. The specification of days
 217 can be made by two fields (day of the month and day of the week). Both are
 218 adhered to if specified as a list of elements. See \fBEXAMPLES\fR.
 219 .sp
 220 .LP
 221 The sixth field of a line in a \fBcrontab\fR file is a string that is executed
 222 by the shell at the specified times. A percent character in this field (unless
 223 escaped by \fB\e\fR\|) is translated to a \fINEWLINE\fR character.
 224 .sp
 225 .LP
 226 Only the first line (up to a \fB`\|%\|'\fR or end of line) of the command field
 227 is executed by the shell. Other lines are made available to the command as
 228 standard input. Any blank line or line beginning with a \fB`\|#\|'\fR is a
 229 comment and is ignored.
 230 .sp
 231 .LP
 232 The shell is invoked from your $HOME directory. As with $TZ, both $SHELL and
 233 $HOME can be set by having a line such as:
 234 .sp
 235 .in +2
 236 .nf
 237 SHELL=/usr/bin/\fIsomeshell\fR
 238 .fi
 239 .in -2
 240 .sp
 241 
 242 .sp
 243 .LP
 244 \&...or:
 245 .sp
 246 .in +2
 247 .nf
 248 HOME=\fIsomedirectory\fR
 249 .fi
 250 .in -2
 251 .sp
 252 
 253 .sp
 254 .LP
 255 \&...which will take precedence for all the remaining entries in the
 256 \fBcrontab\fR or until there is another \fBHOME\fR or \fBSHELL\fR entry. It is
 257 invoked with an \fBarg0\fR of the basename of the $SHELL that is currently in
 258 effect. A user who wants to have his \fB\&.profile\fR or equivalent file
 259 executed must  explicitly do so in the \fBcrontab\fR file. \fBcron\fR supplies
 260 a default environment for every shell, defining HOME, LOGNAME, SHELL, TZ, and
 261 PATH. The default PATH for user \fBcron\fR jobs is \fB/usr/bin\fR; while root
 262 \fBcron\fR jobs default to \fB/usr/sbin:/usr/bin\fR. The default PATH can be
 263 set in \fB/etc/default/cron\fR (see \fBcron\fR(1M)). The TZ, HOME, and SHELL
 264 environment variables are set to match those that are in effect in the
 265 \fBcrontab\fR file at the time.
 266 .sp
 267 .LP
 268 If you do not redirect the standard output and standard error of your commands,
 269 any generated output or errors are mailed to you.
 270 .SS "\fBcrontab\fR Environment Variables"
 271 The following variables are supported:
 272 .sp
 273 .ne 2
 274 .na
 275 \fB\fBHOME\fR\fR
 276 .ad
 277 .sp .6
 278 .RS 4n
 279 Allows the user to choose and alternative directory for cron to change
 280 directory to prior to running the command. For example:
 281 .sp
 282 .in +2
 283 .nf
 284 HOME=/var/tmp
 285 .fi
 286 .in -2
 287 .sp
 288 
 289 .RE
 290 
 291 .sp
 292 .ne 2
 293 .na
 294 \fB\fBSHELL\fR\fR
 295 .ad
 296 .sp .6
 297 .RS 4n
 298 The name of the shell to use to run subsequent commands. For example:
 299 .sp
 300 .in +2
 301 .nf
 302 SHELL=/usr/bin/ksh
 303 .fi
 304 .in -2
 305 .sp
 306 
 307 .RE
 308 
 309 .sp
 310 .ne 2
 311 .na
 312 \fB\fBTZ\fR\fR
 313 .ad
 314 .sp .6
 315 .RS 4n
 316 Allows the user to choose the timezone in which the \fBcron\fR entries are run.
 317 This effects both the environment of the command that is run and the timing of
 318 the entry. For example, to have your entries run using the timezone for
 319 Iceland, use:
 320 .sp
 321 .in +2
 322 .nf
 323 TZ=Iceland
 324 .fi
 325 .in -2
 326 .sp
 327 
 328 .RE
 329 
 330 .sp
 331 .LP
 332 Each of these variables affects all of the lines that follow it in the
 333 \fBcrontab\fR file, until it is reset by a subsequent line resetting that
 334 variable. Hence, it is possible to have multiple timezones supported within a
 335 single \fBcrontab\fR file.
 336 .sp
 337 .LP
 338 The lines that are not setting these environment variables are  the same as
 339 crontab entries that conform to the UNIX standard and are described elsewhere
 340 in this man page.
 341 .SS "Setting \fBcron\fR Jobs Across Timezones"
 342 The default timezone of the \fBcron\fR daemon sets the system-wide timezone for
 343 \fBcron\fR entries. This, in turn, is by set by default system-wide using
 344 \fB/etc/default/init\fR.
 345 .sp
 346 .LP
 347 If some form of \fBdaylight savings\fR or \fBsummer/winter time\fR is in
 348 effect, then jobs scheduled during the switchover period could be executed
 349 once, twice, or not at all.
 350 .SH OPTIONS
 351 The following options are supported:
 352 .sp
 353 .ne 2
 354 .na
 355 \fB\fB-e\fR\fR
 356 .ad
 357 .RS 6n
 358 Edits a copy of the current user's \fBcrontab\fR file, or creates an empty file
 359 to edit if \fBcrontab\fR does not exist. When editing is complete, the file is
 360 installed as the user's \fBcrontab\fR file.
 361 .sp
 362 The environment variable \fBEDITOR\fR determines which editor is invoked with
 363 the \fB-e\fR option. All \fBcrontab\fR jobs should be submitted using
 364 \fBcrontab\fR. Do not add jobs by just editing the \fBcrontab\fR file, because
 365 \fBcron\fR is not aware of changes made this way.
 366 .sp
 367 If all lines in the \fBcrontab\fR file are deleted, the old \fBcrontab\fR file
 368 is restored. The correct way to delete all lines is to remove the \fBcrontab\fR
 369 file using the \fB-r\fR option.
 370 .sp
 371 If \fIusername\fR is specified, the specified user's \fBcrontab\fR file is
 372 edited, rather than the current user's \fBcrontab\fR file. This can only be
 373 done by root or by a user with the \fBsolaris.jobs.admin\fR authorization.
 374 .RE
 375 
 376 .sp
 377 .ne 2
 378 .na
 379 \fB\fB-l\fR\fR
 380 .ad
 381 .RS 6n
 382 Lists the \fBcrontab\fR file for the invoking user. Only root or a user with
 383 the \fBsolaris.jobs.admin\fR authorization can specify a username following the
 384 \fB-l\fR option to list the \fBcrontab\fR file of the specified user.
 385 .RE
 386 
 387 .sp
 388 .ne 2
 389 .na
 390 \fB\fB-r\fR\fR
 391 .ad
 392 .RS 6n
 393 Removes a user's \fBcrontab\fR from the \fBcrontab\fR directory. Only root or a
 394 user with the \fBsolaris.jobs.admin\fR authorization can specify a username
 395 following the \fB-r\fR option to remove the \fBcrontab\fR file of the specified
 396 user.
 397 .RE
 398 
 399 .SH EXAMPLES
 400 \fBExample 1 \fRCleaning up Core Files
 401 .sp
 402 .LP
 403 This example cleans up \fBcore\fR files every weekday morning at 3:15 am:
 404 
 405 .sp
 406 .in +2
 407 .nf
 408 \fB15 3 * * 1-5 find $HOME\fR \fB-name\fR\fBcore 2>/dev/null | xargs rm\fR \fB-f\fR
 409 .fi
 410 .in -2
 411 .sp
 412 
 413 .LP
 414 \fBExample 2 \fRMailing a Birthday Greeting
 415 .sp
 416 .LP
 417 This example mails a birthday greeting:
 418 
 419 .sp
 420 .in +2
 421 .nf
 422 \fB0 12 14 2 * mailx john%Happy Birthday!%Time for lunch.\fR
 423 .fi
 424 .in -2
 425 .sp
 426 
 427 .LP
 428 \fBExample 3 \fRSpecifying Days of the Month and Week
 429 .sp
 430 .LP
 431 This example runs a command on the first and fifteenth of each month, as well
 432 as on every Monday:
 433 
 434 .sp
 435 .in +2
 436 .nf
 437 \fB0 0 1,15 * 1\fR
 438 .fi
 439 .in -2
 440 .sp
 441 
 442 .sp
 443 .LP
 444 To specify days by only one field, the other field should be set to *. For
 445 example:
 446 
 447 .sp
 448 .in +2
 449 .nf
 450 \fB0 0 * * 1\fR
 451 .fi
 452 .in -2
 453 .sp
 454 
 455 .sp
 456 .LP
 457 would run a command only on Mondays.
 458 
 459 .LP
 460 \fBExample 4 \fRUsing step values:
 461 .sp
 462 .LP
 463 This example runs a job every hour during the night and every 3 hours during
 464 working hours.
 465 
 466 .sp
 467 .in +2
 468 .nf
 469 \fB0 8-18/3,19-7 * * *\fR
 470 .fi
 471 .in -2
 472 .sp
 473 
 474 .LP
 475 and to run a job every 2 minutes, use:
 476 
 477 .sp
 478 .in +2
 479 .nf
 480 \fB*/2 * * * *\fR
 481 .fi
 482 .in -2
 483 .sp
 484 
 485 .LP
 486 \fBExample 5 \fRUsing Environment Variables
 487 .sp
 488 .LP
 489 The following entries take advantage of \fBcrontab\fR support for certain
 490 environment variables.
 491 
 492 .sp
 493 .in +2
 494 .nf
 495 TZ=GMT
 496 HOME=/local/home/user
 497 SHELL=/usr/bin/ksh
 498 0 0 * * * echo $(date) >        midnight.GMT
 499 TZ=PST
 500 0 0 * * * echo $(date) >        midnight.PST
 501 TZ=EST
 502 HOME=/local/home/myuser
 503 SHELL=/bin/csh
 504 .fi
 505 .in -2
 506 .sp
 507 
 508 .sp
 509 .LP
 510 The preceding entries allow two jobs to run. The first one would run at
 511 midnight in the GMT timezone and the second would run at midnight in the PST
 512 timezone. Both would be run in the directory \fB/local/home/user\fR using the
 513 Korn shell. The file concludes with \fBTZ\fR, \fBHOME\fR, and \fBSHELL\fR
 514 entries that return those variable to their default values.
 515 
 516 .SH ENVIRONMENT VARIABLES
 517 See \fBenviron\fR(5) for descriptions of the following environment variables
 518 that affect the execution of \fBcrontab\fR: \fBLANG\fR, \fBLC_ALL\fR,
 519 \fBLC_CTYPE\fR, \fBLC_MESSAGES\fR, and \fBNLSPATH\fR.
 520 .SS "\fB/usr/bin/crontab\fR"
 521 .ne 2
 522 .na
 523 \fB\fBEDITOR\fR\fR
 524 .ad
 525 .RS 10n
 526 Determine the editor to be invoked when the \fB-e\fR option is specified. This
 527 is overridden by the \fBVISUAL\fR environmental variable. The default editor is
 528 \fBvi\fR(1).
 529 .RE
 530 
 531 .sp
 532 .ne 2
 533 .na
 534 \fB\fBPATH\fR\fR
 535 .ad
 536 .RS 10n
 537 The \fBPATH\fR in \fBcrontab\fR's environment specifies the search path used to
 538 find the editor.
 539 .RE
 540 
 541 .sp
 542 .ne 2
 543 .na
 544 \fB\fBVISUAL\fR\fR
 545 .ad
 546 .RS 10n
 547 Determine the visual editor to be invoked when the \fB-e\fR option is
 548 specified. If \fBVISUAL\fR is not specified, then the environment variable
 549 \fBEDITOR\fR is used. If that is not set, the default is \fBvi\fR(1).
 550 .RE
 551 
 552 .SS "\fB/usr/xpg4/bin/crontab\fR"
 553 .ne 2
 554 .na
 555 \fB\fBEDITOR\fR\fR
 556 .ad
 557 .RS 10n
 558 Determine the editor to be invoked when the \fB-e\fR option is specified. The
 559 default editor is \fB/usr/xpg4/bin/vi\fR.
 560 .RE
 561 
 562 .SS "\fB/usr/xpg6/bin/crontab\fR"
 563 .ne 2
 564 .na
 565 \fB\fBEDITOR\fR\fR
 566 .ad
 567 .RS 10n
 568 Determine the editor to be invoked when the \fB-e\fR option is specified. The
 569 default editor is \fB/usr/xpg6/bin/vi\fR.
 570 .RE
 571 
 572 .SH EXIT STATUS
 573 The following exit values are returned:
 574 .sp
 575 .ne 2
 576 .na
 577 \fB\fB0\fR\fR
 578 .ad
 579 .RS 6n
 580 Successful completion.
 581 .RE
 582 
 583 .sp
 584 .ne 2
 585 .na
 586 \fB\fB>0\fR\fR
 587 .ad
 588 .RS 6n
 589 An error occurred.
 590 .RE
 591 
 592 .SH FILES
 593 .ne 2
 594 .na
 595 \fB\fB/etc/cron.d\fR\fR
 596 .ad
 597 .RS 28n
 598 main cron directory
 599 .RE
 600 
 601 .sp
 602 .ne 2
 603 .na
 604 \fB\fB/etc/cron.d/cron.allow\fR\fR
 605 .ad
 606 .RS 28n
 607 list of allowed users
 608 .RE
 609 
 610 .sp
 611 .ne 2
 612 .na
 613 \fB\fB/etc/default/cron\fR\fR
 614 .ad
 615 .RS 28n
 616 contains cron default settings
 617 .RE
 618 
 619 .sp
 620 .ne 2
 621 .na
 622 \fB\fB/etc/cron.d/cron.deny\fR\fR
 623 .ad
 624 .RS 28n
 625 list of denied users
 626 .RE
 627 
 628 .sp
 629 .ne 2
 630 .na
 631 \fB\fB/var/cron/log\fR\fR
 632 .ad
 633 .RS 28n
 634 accounting information
 635 .RE
 636 
 637 .sp
 638 .ne 2
 639 .na
 640 \fB\fB/var/spool/cron/crontabs\fR\fR
 641 .ad
 642 .RS 28n
 643 spool area for \fBcrontab\fR
 644 .RE
 645 
 646 .SH ATTRIBUTES
 647 See \fBattributes\fR(5) for descriptions of the following attributes:
 648 .SS "\fB/usr/bin/crontab\fR"
 649 
 650 .TS
 651 box;
 652 c | c
 653 l | l .
 654 ATTRIBUTE TYPE  ATTRIBUTE VALUE
 655 _
 656 Interface Stability     Standard
 657 .TE
 658 
 659 .SS "\fB/usr/xpg4/bin/crontab\fR"
 660 
 661 .TS
 662 box;
 663 c | c
 664 l | l .
 665 ATTRIBUTE TYPE  ATTRIBUTE VALUE
 666 _
 667 Interface Stability     Standard
 668 .TE
 669 
 670 .SS "\fB/usr/xpg6/bin/crontab\fR"
 671 
 672 .TS
 673 box;
 674 c | c
 675 l | l .
 676 ATTRIBUTE TYPE  ATTRIBUTE VALUE
 677 _
 678 Interface Stability     Standard
 679 .TE
 680 
 681 .SH SEE ALSO
 682 \fBatq\fR(1), \fBatrm\fR(1), \fBauths\fR(1), \fBed\fR(1), \fBsh\fR(1),
 683 \fBvi\fR(1), \fBcron\fR(1M), \fBsu\fR(1M), \fBauth_attr\fR(4),
 684 \fBattributes\fR(5), \fBenviron\fR(5), \fBstandards\fR(5)
 685 .SH NOTES
 686 If you inadvertently enter the \fBcrontab\fR command with no arguments, do not
 687 attempt to get out with Control-d. This removes all entries in your
 688 \fBcrontab\fR file. Instead, exit with Control-c.
 689 .sp
 690 .LP
 691 When updating \fBcron\fR, check first for existing \fBcrontab\fR entries that
 692 can be scheduled close to the time of the update. Such entries can be lost if
 693 the update process completes after the scheduled event. This can happen
 694 because, when \fBcron\fR is notified by \fBcrontab\fR to update the internal
 695 view of a user's \fBcrontab\fR file, it first removes the user's existing
 696 internal \fBcrontab\fR and any internal scheduled events. Then it reads the new
 697 \fBcrontab\fR file and rebuilds the internal \fBcrontab\fR and events. This
 698 last step takes time, especially with a large \fBcrontab\fR file, and can
 699 complete \fBafter\fR an existing \fBcrontab\fR entry is scheduled to run if it
 700 is scheduled too close to the update. To be safe, start a new job at least 60
 701 seconds after the current date and time.
 702 .sp
 703 .LP
 704 If an authorized user other than root modifies another user's \fBcrontab\fR
 705 file, the resulting behavior can be unpredictable. Instead, the authorized user
 706 should first use \fBsu\fR(1M) to become superuser to the other user's login
 707 before making any changes to the \fBcrontab\fR file.
 708 .sp
 709 .LP
 710 Care should be taken when adding \fBTZ\fR, \fBSHELL\fR and \fBHOME\fR variables
 711 to the \fBcrontab\fR  file when the \fBcrontab\fR file could be shared with
 712 applications that do not expect those variables to be changed from the default.
 713 Resetting the values to their defaults at the bottom of the file will minimize
 714 the risk of problems.