|| Linux Programmer's Manual
NAME unlink - delete a name and possibly the file it refers to
int unlink(const char *
() deletes a name from the file system. If that name was the last link to a file and no processes have the file open the file is deleted and the space it was using is made available for reuse.
If the name was the last link to a file but any processes still have the file open the file will remain in existence until the last file descriptor referring to it is closed.
If the name referred to a symbolic link the link is removed.
If the name referred to a socket, fifo or device the name for it is removed but processes which have the object open may continue to use it.
RETURN VALUE On success, zero is returned. On error, -1 is returned, and
errno is set appropriately.
Write access to the directory containing
pathname is not allowed for the process's effective UID, or one of the directories in
pathname did not allow search permission. (See also
pathname cannot be unlinked because it is being used by the system or another process; for example, it is a mount point or the NFS client software created it to represent an active but otherwise nameless inode ("NFS silly renamed").
pathname points outside your accessible address space.
An I/O error occurred.
pathname refers to a directory. (This is the non-POSIX value returned by Linux since 2.1.132.)
Too many symbolic links were encountered in translating
pathname was too long.
A component in
pathname does not exist or is a dangling symbolic link, or
pathname is empty.
Insufficient kernel memory was available.
A component used as a directory in
pathname is not, in fact, a directory.
The system does not allow unlinking of directories, or unlinking of directories requires privileges that the calling process doesn't have. (This is the POSIX prescribed error return; as noted above, Linux returns
EISDIR for this case.)
EPERM (Linux only)
The file system does not allow unlinking of files.
The directory containing
pathname has the sticky bit (
S_ISVTX) set and the process's effective UID is neither the UID of the file to be deleted nor that of the directory containing it, and the process is not privileged (Linux: does not have the
pathname refers to a file on a read-only file system.
CONFORMING TO SVr4, 4.3BSD, POSIX.1-2001.
BUGS Infelicities in the protocol underlying NFS can cause the unexpected disappearance of files which are still being used.
COLOPHON This page is part of release 3.53 of the Linux
man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.