unlink()
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.
ERRORS
EACCES
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
path_resolution(7).)
EBUSY (not on Linux)
The file
pathname
cannot be unlinked because it is being used by the system
or another process and the implementation considers this an error.
EFAULT
pathname
points outside your accessible address space.
EIO
An I/O error occurred.
EISDIR
pathname
refers to a directory.
(This is the non-POSIX value returned by Linux since 2.1.132.)
ELOOP
Too many symbolic links were encountered in translating
pathname.
ENAMETOOLONG
pathname was too long.
ENOENT
A component in
pathname
does not exist or is a dangling symbolic link, or
pathname
is empty.
ENOMEM
Insufficient kernel memory was available.
ENOTDIR
A component used as a directory in
pathname
is not, in fact, a directory.
EPERM
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.
EPERM or EACCES
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
CAP_FOWNER
capability).
EROFS
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.
This page is part of release 3.14 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/.