Deletion actually deletes a file name. If this is the file's only name,
then the file is deleted as well. If the file has other remaining names
(see Hard Links), it remains accessible under those names.
— Function: int unlink (const char *filename)
The unlink function deletes the file name filename. If
this is a file's sole name, the file itself is also deleted. (Actually,
if any process has the file open when this happens, deletion is
postponed until all processes have closed the file.)
The function unlink is declared in the header file unistd.h.
This function returns 0 on successful completion, and -1
on error. In addition to the usual file name errors
(see File Name Errors), the following errno error conditions are
defined for this function:
EACCES
Write permission is denied for the directory from which the file is to be
removed, or the directory has the sticky bit set and you do not own the file.
EBUSY
This error indicates that the file is being used by the system in such a
way that it can't be unlinked. For example, you might see this error if
the file name specifies the root directory or a mount point for a file
system.
ENOENT
The file name to be deleted doesn't exist.
EPERM
On some systems unlink cannot be used to delete the name of a
directory, or at least can only be used this way by a privileged user.
To avoid such problems, use rmdir to delete directories. (In the
GNU system unlink can never delete the name of a directory.)
EROFS
The directory containing the file name to be deleted is on a read-only
file system and can't be modified.
— Function: int rmdir (const char *filename)
The rmdir function deletes a directory. The directory must be
empty before it can be removed; in other words, it can only contain
entries for . and ...
In most other respects, rmdir behaves like unlink. There
are two additional errno error conditions defined for
rmdir:
ENOTEMPTY
EEXIST
The directory to be deleted is not empty.
These two error codes are synonymous; some systems use one, and some use
the other. The GNU system always uses ENOTEMPTY.
The prototype for this function is declared in the header file
unistd.h.
— Function: int remove (const char *filename)
This is the ISO C function to remove a file. It works like
unlink for files and like rmdir for directories.
remove is declared in stdio.h.
Published under the terms of the GNU General Public License
