NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | USAGE | ATTRIBUTES | SUMMARY OF TRUSTED SOLARIS CHANGES | SEE ALSO
#include <unistd.h>int unlink(const char *path);
The unlink() function removes a link to a file. If path names a symbolic link, unlink() removes the symbolic link named by path and does not affect any file or directory named by the contents of the symbolic link. Otherwise, unlink() removes the link named by the pathname pointed to by path and decrements the link count of the file referenced by the link.
When the file's link count becomes 0 and no process has the file open, the space occupied by the file will be freed and the file will no longer be accessible. If one or more processes have the file open when the last link is removed, the link will be removed before unlink() returns, but the removal of the file contents will be postponed until all references to the file are closed.
The path argument must not name a directory unless the process has asserted the PRIV_SYS_CONFIG
privilege and the implementation supports using unlink() on directories.
Upon successful completion, unlink() will mark for update the st_ctime and st_mtime fields of the parent directory. If the file's link count is not 0, the st_ctime field of the file will be marked for update.
Upon successful completion, 0 is returned. Otherwise, -1 is returned, errno is set to indicate the error, and the file is not unlinked.
The unlink() function will fail if:
Search permission is denied for a component of the path prefix.
Write permission is denied on the directory containing the link to be removed. To override this restriction, the calling process must assert one or both of these privileges: PRIV_FILE_DAC_WRITE
and PRIV_FILE_MAC_WRITE
.
The parent directory has the sticky bit set and the file is not writable by the user; or the user does not own the parent directory and the user does not own the file. To override this restriction, the calling process must assert one or more of these privileges: PRIV_FILE_DAC_WRITE
, PRIV_FILE_MAC_WRITE
, and PRIV_FILE_OWNER
.
The entry to be unlinked is the mount point for a mounted file system.
The path argument points to an illegal address.
A signal was caught during the execution of the unlink() function.
Too many symbolic links were encountered in translating path.
The length of the path argument exceeds PATH_MAX, or the length of a path component exceeds NAME_MAX while _POSIX_NO_TRUNC is in effect.
The named file does not exist or is a null pathname.
The path argument points to a remote machine and the link to that machine is no longer active.
A component of the path prefix is not a directory.
The named file is a directory and the calling process must assert the PRIV_SYS_CONFIG
privilege.
The directory entry to be unlinked is part of a read-only file system.
The unlink() function may fail if:
Pathname resolution of a symbolic link produced an intermediate result whose length exceeds PATH_MAX.
The entry to be unlinked is the last directory entry to a pure procedure (shared text) file that is being executed.
Applications should use rmdir(2) to remove a directory.
See attributes(5) for descriptions of the following attributes:
ATTRIBUTE TYPE | ATTRIBUTE VALUE |
---|---|
MT-Level | Async-Signal-Safe |
Appropriate privilege is required to override access checks.
If the named file is a directory, the calling process must assert the PRIV_SYS_CONFIG
privilege.
NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | USAGE | ATTRIBUTES | SUMMARY OF TRUSTED SOLARIS CHANGES | SEE ALSO