NAME
unlink
—
remove directory entry
LIBRARY
library “libc”
SYNOPSIS
#include
<unistd.h>
int
unlink
(const
char *path);
DESCRIPTION
Theunlink
()
function removes the link named by path from its
directory and decrements the link count of the file which was referenced by
the link. If that decrement reduces the link count of the file to zero, and no
process has the file open, then all resources associated with the file are
reclaimed. If one or more process have the file open when the last link is
removed, the link is removed, but the removal of the file is delayed until all
references to it have been closed. path may not be a
directory.
RETURN VALUES
The unlink
() function returns the
value 0 if successful; otherwise the value -1 is returned and
the global variable errno is set to indicate the
error.
ERRORS
The unlink
() succeeds unless:
- [
ENOTDIR
] - A component of the path prefix is not a directory.
- [
ENAMETOOLONG
] - A component of a pathname exceeded 255 characters, or an entire path name exceeded 1023 characters.
- [
ENOENT
] - The named file does not exist.
- [
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.
- [
ELOOP
] - Too many symbolic links were encountered in translating the pathname.
- [
EPERM
] - The named file has its immutable or append-only flag set (see chflags(2)).
- [
EPERM
] - The named file is a directory.
- [
EPERM
] - The directory containing the file is marked sticky, and neither the containing directory nor the file to be removed are owned by the effective user ID.
- [
EBUSY
] - The entry to be unlinked is the mount point for a mounted file system.
- [
EIO
] - An I/O error occurred while deleting the directory entry or deallocating the inode.
- [
EROFS
] - The named file resides on a read-only file system.
- [
EFAULT
] - Path points outside the process's allocated address space.
SEE ALSO
HISTORY
An unlink
() function call appeared in
Version 6 AT&T UNIX.
The unlink
() system call traditionally
allows the super-user to unlink directories which can damage the filesystem
integrity. This implementation no longer permits it.