unlink(2) unlink(2)
NAME
unlink - remove directory entry
SYNOPSIS
#include <unistd.h>
int unlink(const char *path);
DESCRIPTION
unlink removes the directory entry named by the path name pointed to
by path. and decrements the link count of the file referenced by the
directory entry. When all links to a file have been removed and no
process has the file open, the space occupied by the file is freed
and the file ceases to exist. If one or more processes have the file
open when the last link is removed, space occupied by the file is not
released until all references to the file have been closed. If path
is a symbolic link, the symbolic link is removed. path should not
name a directory unless the process has appropriate privileges.
Applications should use rmdir to remove directories.
Upon successful completion unlink marks for update the stctime and
stmtime fields of the parent directory. Also, if the file's link
count is not zero, the stctime field of the file is marked for
update.
The named file is unlinked unless one or more of the following are
true:
EACCES Search permission is denied for a component of
the path prefix.
EACCES Write permission is denied on the directory
containing the link to be removed.
EACCES The parent directory has the sticky bit set and
the file is not writable by the user; the user
does not own the parent directory and the user
does not own the file;
EBUSY The entry to be unlinked is the mount point for a
mounted file system.
EFAULT path points outside the process's allocated
address space.
EINTR A signal was caught during the unlink system
call.
ELOOP Too many symbolic links were encountered in
translating path.
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unlink(2) unlink(2)
EMULTIHOP Components of path require hopping to multiple
remote machines and the file system does not
allow it.
ENAMETOOLONG The length of the path argument exceeds
{PATHMAX}, or the length of a path component
exceeds {NAMEMAX} while POSIXNOTRUNC is in
effect.
ENOENT The named file does not exist or is a null
pathname. The user is not a super-user.
ENOTDIR A component of the path prefix is not a
directory.
EPERM The named file is a directory and the effective
user ID of the process is not super-user.
ETXTBSY The entry to be unlinked is the last link to a
pure procedure (shared text) file that is being
executed.
EROFS The directory entry to be unlinked is part of a
read-only file system.
ENOLINK path points to a remote machine and the link to
that machine is no longer active.
SEE ALSO
close(2), link(2), open(2), rmdir(2).
rm(1) in the User's Reference Manual.
DIAGNOSTICS
Upon successful completion, a value of 0 is returned. Otherwise, a
value of -1 is returned and errno is set to indicate the error.
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