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4841 - lockf(3c): Minor formatting issues in man page
*** 33,44 ****
The \fIfildes\fR argument is an open file descriptor. The file descriptor must
have \fBO_WRONLY\fR or \fBO_RDWR\fR permission in order to establish locks with
this function call.
.sp
.LP
! The \fBfunction\fR argument is a control value that specifies the action to be
! taken. The permissible values for \fBfunction\fR are defined in
<\fBunistd.h\fR> as follows:
.sp
.in +2
.nf
#define F_ULOCK 0 /* unlock previously locked section */
--- 33,44 ----
The \fIfildes\fR argument is an open file descriptor. The file descriptor must
have \fBO_WRONLY\fR or \fBO_RDWR\fR permission in order to establish locks with
this function call.
.sp
.LP
! The \fIfunction\fR argument is a control value that specifies the action to be
! taken. The permissible values for \fIfunction\fR are defined in
<\fBunistd.h\fR> as follows:
.sp
.in +2
.nf
#define F_ULOCK 0 /* unlock previously locked section */
*** 48,81 ****
.fi
.in -2
.sp
.LP
! All other values of \fBfunction\fR are reserved for future extensions and will
result in an error if not implemented.
.sp
.LP
\fBF_TEST\fR is used to detect if a lock by another process is present on the
specified section. \fBF_LOCK\fR and \fBF_TLOCK\fR both lock a section of a file
if the section is available. \fBF_ULOCK\fR removes locks from a section of the
file.
.sp
.LP
! The \fBsize\fR argument is the number of contiguous bytes to be locked or
unlocked. The resource to be locked or unlocked starts at the current offset in
! the file and extends forward for a positive size and backward for a negative
! size (the preceding bytes up to but not including the current offset). If
! \fBsize\fR is zero, the section from the current offset through the largest
file offset is locked (that is, from the current offset through the present or
any future end-of-file). An area need not be allocated to the file in order to
be locked as such locks may exist past the end-of-file.
.sp
.LP
The sections locked with \fBF_LOCK\fR or \fBF_TLOCK\fR may, in whole or in
part, contain or be contained by a previously locked section for the same
process. Locked sections will be unlocked starting at the point of the offset
! through \fBsize\fR bytes or to the end of file if \fBsize\fR is (\fBoff_t\fR)
0. When this situation occurs, or if this situation occurs in adjacent
sections, the sections are combined into a single section. If the request
requires that a new element be added to the table of active locks and this
table is already full, an error is returned, and the new section is not locked.
.sp
--- 48,81 ----
.fi
.in -2
.sp
.LP
! All other values of \fIfunction\fR are reserved for future extensions and will
result in an error if not implemented.
.sp
.LP
\fBF_TEST\fR is used to detect if a lock by another process is present on the
specified section. \fBF_LOCK\fR and \fBF_TLOCK\fR both lock a section of a file
if the section is available. \fBF_ULOCK\fR removes locks from a section of the
file.
.sp
.LP
! The \fIsize\fR argument is the number of contiguous bytes to be locked or
unlocked. The resource to be locked or unlocked starts at the current offset in
! the file and extends forward for a positive \fIsize\fR and backward for a negative
! \fIsize\fR (the preceding bytes up to but not including the current offset). If
! \fIsize\fR is zero, the section from the current offset through the largest
file offset is locked (that is, from the current offset through the present or
any future end-of-file). An area need not be allocated to the file in order to
be locked as such locks may exist past the end-of-file.
.sp
.LP
The sections locked with \fBF_LOCK\fR or \fBF_TLOCK\fR may, in whole or in
part, contain or be contained by a previously locked section for the same
process. Locked sections will be unlocked starting at the point of the offset
! through \fIsize\fR bytes or to the end of file if \fIsize\fR is (\fBoff_t\fR)
0. When this situation occurs, or if this situation occurs in adjacent
sections, the sections are combined into a single section. If the request
requires that a new element be added to the table of active locks and this
table is already full, an error is returned, and the new section is not locked.
.sp
*** 97,111 ****
section of a locked section requires an additional element in the table of
active locks. If this table is full, an \fBerrno\fR is set to \fBEDEADLK\fR and
the requested section is not released.
.sp
.LP
! An \fBF_ULOCK\fR request in which \fBsize\fR is non-zero and the offset of the
last byte of the requested section is the maximum value for an object of type
! \fBoff_t\fR, when the process has an existing lock in which \fBsize\fR is 0 and
which includes the last byte of the requested section, will be treated as a
! request to unlock from the start of the requested section with a size equal to
0. Otherwise, an \fBF_ULOCK\fR request will attempt to unlock only the
requested section.
.sp
.LP
A potential for deadlock occurs if the threads of a process controlling a
--- 97,111 ----
section of a locked section requires an additional element in the table of
active locks. If this table is full, an \fBerrno\fR is set to \fBEDEADLK\fR and
the requested section is not released.
.sp
.LP
! An \fBF_ULOCK\fR request in which \fIsize\fR is non-zero and the offset of the
last byte of the requested section is the maximum value for an object of type
! \fBoff_t\fR, when the process has an existing lock in which \fIsize\fR is 0 and
which includes the last byte of the requested section, will be treated as a
! request to unlock from the start of the requested section with a \fIsize\fR equal to
0. Otherwise, an \fBF_ULOCK\fR request will attempt to unlock only the
requested section.
.sp
.LP
A potential for deadlock occurs if the threads of a process controlling a
*** 132,162 ****
.na
\fB\fBEBADF\fR\fR
.ad
.RS 20n
The \fIfildes\fR argument is not a valid open file descriptor; or
! \fBfunction\fR is \fBF_LOCK\fR or \fBF_TLOCK\fR and \fIfildes\fR is not a valid
file descriptor open for writing.
.RE
.sp
.ne 2
.na
\fB\fBEACCES\fR or \fBEAGAIN\fR\fR
.ad
.RS 20n
! The \fBfunction\fR argument is \fBF_TLOCK\fR or \fBF_TEST\fR and the section is
already locked by another process.
.RE
.sp
.ne 2
.na
\fB\fBEDEADLK\fR\fR
.ad
.RS 20n
! The \fBfunction\fR argument is \fBF_LOCK\fR and a deadlock is detected.
.RE
.sp
.ne 2
.na
--- 132,162 ----
.na
\fB\fBEBADF\fR\fR
.ad
.RS 20n
The \fIfildes\fR argument is not a valid open file descriptor; or
! \fIfunction\fR is \fBF_LOCK\fR or \fBF_TLOCK\fR and \fIfildes\fR is not a valid
file descriptor open for writing.
.RE
.sp
.ne 2
.na
\fB\fBEACCES\fR or \fBEAGAIN\fR\fR
.ad
.RS 20n
! The \fIfunction\fR argument is \fBF_TLOCK\fR or \fBF_TEST\fR and the section is
already locked by another process.
.RE
.sp
.ne 2
.na
\fB\fBEDEADLK\fR\fR
.ad
.RS 20n
! The \fIfunction\fR argument is \fBF_LOCK\fR and a deadlock is detected.
.RE
.sp
.ne 2
.na
*** 180,201 ****
.ne 2
.na
\fB\fBEINVAL\fR\fR
.ad
.RS 20n
! The \fBfunction\fR argument is not one of \fBF_LOCK\fR, \fBF_TLOCK\fR,
! \fBF_TEST\fR, or \fBF_ULOCK\fR; or \fBsize\fR plus the current file offset is
less than 0.
.RE
.sp
.ne 2
.na
\fB\fBEOVERFLOW\fR\fR
.ad
.RS 20n
! The offset of the first, or if \fBsize\fR is not 0 then the last, byte in the
requested section cannot be represented correctly in an object of type
\fBoff_t\fR.
.RE
.sp
--- 180,201 ----
.ne 2
.na
\fB\fBEINVAL\fR\fR
.ad
.RS 20n
! The \fIfunction\fR argument is not one of \fBF_LOCK\fR, \fBF_TLOCK\fR,
! \fBF_TEST\fR, or \fBF_ULOCK\fR; or \fIsize\fR plus the current file offset is
less than 0.
.RE
.sp
.ne 2
.na
\fB\fBEOVERFLOW\fR\fR
.ad
.RS 20n
! The offset of the first, or if \fIsize\fR is not 0 then the last, byte in the
requested section cannot be represented correctly in an object of type
\fBoff_t\fR.
.RE
.sp
*** 205,225 ****
.ne 2
.na
\fB\fBEAGAIN\fR\fR
.ad
.RS 24n
! The \fBfunction\fR argument is \fBF_LOCK\fR or \fBF_TLOCK\fR and the file is
mapped with \fBmmap\fR(2).
.RE
.sp
.ne 2
.na
\fB\fBEDEADLK\fR or \fBENOLCK\fR\fR
.ad
.RS 24n
! The \fBfunction\fR argument is \fBF_LOCK\fR, \fBF_TLOCK\fR, or \fBF_ULOCK\fR
and the request would cause the number of locks to exceed a system-imposed
limit.
.RE
.sp
--- 205,225 ----
.ne 2
.na
\fB\fBEAGAIN\fR\fR
.ad
.RS 24n
! The \fIfunction\fR argument is \fBF_LOCK\fR or \fBF_TLOCK\fR and the file is
mapped with \fBmmap\fR(2).
.RE
.sp
.ne 2
.na
\fB\fBEDEADLK\fR or \fBENOLCK\fR\fR
.ad
.RS 24n
! The \fIfunction\fR argument is \fBF_LOCK\fR, \fBF_TLOCK\fR, or \fBF_ULOCK\fR
and the request would cause the number of locks to exceed a system-imposed
limit.
.RE
.sp