unlink(2) SYSTEM CALLS 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 follow-
ing are true:
EACCES Search permission is denied for a com-
ponent of the path prefix.
EACCES Write permission is denied on the direc-
tory 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 allo-
cated 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) SYSTEM CALLS 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 com-
ponent 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. Oth-
erwise, a value of -1 is returned and errno is set to indi-
cate the error.
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