diff options
Diffstat (limited to 'man3/lockf.3')
| -rw-r--r-- | man3/lockf.3 | 179 |
1 files changed, 0 insertions, 179 deletions
diff --git a/man3/lockf.3 b/man3/lockf.3 deleted file mode 100644 index f8b005f..0000000 --- a/man3/lockf.3 +++ /dev/null @@ -1,179 +0,0 @@ -'\" t -.\" Copyright 1997 Nicolás Lichtmaier <nick@debian.org> -.\" Created Thu Aug 7 00:44:00 ART 1997 -.\" -.\" SPDX-License-Identifier: GPL-2.0-or-later -.\" -.\" Added section stuff, aeb, 2002-04-22. -.\" Corrected include file, drepper, 2003-06-15. -.\" -.TH lockf 3 2024-03-03 "Linux man-pages 6.7" -.SH NAME -lockf \- apply, test or remove a POSIX lock on an open file -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <unistd.h> -.P -.BI "int lockf(int " fd ", int " op ", off_t " len ); -.fi -.P -.RS -4 -Feature Test Macro Requirements for glibc (see -.BR feature_test_macros (7)): -.RE -.P -.BR lockf (): -.nf - _XOPEN_SOURCE >= 500 -.\" || _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED - || /* glibc >= 2.19: */ _DEFAULT_SOURCE - || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE -.fi -.SH DESCRIPTION -Apply, test, or remove a POSIX lock on a section of an open file. -The file is specified by -.IR fd , -a file descriptor open for writing, the action by -.IR op , -and the section consists of byte positions -.IR pos .. pos + len \-1 -if -.I len -is positive, and -.IR pos \- len .. pos \-1 -if -.I len -is negative, where -.I pos -is the current file position, and if -.I len -is zero, the section extends from the current file position to -infinity, encompassing the present and future end-of-file positions. -In all cases, the section may extend past current end-of-file. -.P -On Linux, -.BR lockf () -is just an interface on top of -.BR fcntl (2) -locking. -Many other systems implement -.BR lockf () -in this way, but note that POSIX.1 leaves the relationship between -.BR lockf () -and -.BR fcntl (2) -locks unspecified. -A portable application should probably avoid mixing calls -to these interfaces. -.P -Valid operations are given below: -.TP -.B F_LOCK -Set an exclusive lock on the specified section of the file. -If (part of) this section is already locked, the call -blocks until the previous lock is released. -If this section overlaps an earlier locked section, -both are merged. -File locks are released as soon as the process holding the locks -closes some file descriptor for the file. -A child process does not inherit these locks. -.TP -.B F_TLOCK -Same as -.B F_LOCK -but the call never blocks and returns an error instead if the file is -already locked. -.TP -.B F_ULOCK -Unlock the indicated section of the file. -This may cause a locked section to be split into two locked sections. -.TP -.B F_TEST -Test the lock: return 0 if the specified section -is unlocked or locked by this process; return \-1, set -.I errno -to -.B EAGAIN -.RB ( EACCES -on some other systems), -if another process holds a lock. -.SH RETURN VALUE -On success, zero is returned. -On error, \-1 is returned, and -.I errno -is set to indicate the error. -.SH ERRORS -.TP -.BR EACCES " or " EAGAIN -The file is locked and -.B F_TLOCK -or -.B F_TEST -was specified, or the operation is prohibited because the file has -been memory-mapped by another process. -.TP -.B EBADF -.I fd -is not an open file descriptor; or -.I op -is -.B F_LOCK -or -.B F_TLOCK -and -.I fd -is not a writable file descriptor. -.TP -.B EDEADLK -.I op -was -.B F_LOCK -and this lock operation would cause a deadlock. -.TP -.B EINTR -While waiting to acquire a lock, the call was interrupted by -delivery of a signal caught by a handler; see -.BR signal (7). -.TP -.B EINVAL -An invalid operation was specified in -.IR op . -.TP -.B ENOLCK -Too many segment locks open, lock table is full. -.SH ATTRIBUTES -For an explanation of the terms used in this section, see -.BR attributes (7). -.TS -allbox; -lbx lb lb -l l l. -Interface Attribute Value -T{ -.na -.nh -.BR lockf () -T} Thread safety MT-Safe -.TE -.SH STANDARDS -POSIX.1-2008. -.SH HISTORY -POSIX.1-2001, SVr4. -.SH SEE ALSO -.BR fcntl (2), -.BR flock (2) -.P -.I locks.txt -and -.I mandatory\-locking.txt -in the Linux kernel source directory -.I Documentation/filesystems -(on older kernels, these files are directly under the -.I Documentation -directory, and -.I mandatory\-locking.txt -is called -.IR mandatory.txt ) |