unlink — delete a name and possibly the file it refers to
#include <unistd.h>
int
unlink( |
const char * | pathname); |
unlink() deletes a name from
the filesystem. 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.
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 path_resolution(7).)
The file pathname cannot be
unlinked because it is being used by the system or
another process and the implementation considers this
an error.
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.
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.)
The filesystem 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 CAP_FOWNER
capability).
pathname
refers to a file on a read-only filesystem.
Infelicities in the protocol underlying NFS can cause the unexpected disappearance of files which are still being used.
rm(1), chmod(2), link(2), mknod(2), open(2), rename(2), rmdir(2), unlinkat(2), mkfifo(3), remove(3), path_resolution(7)