redhat man page for unlink

UNLINK(2)						     Linux Programmer's Manual							 UNLINK(2)

NAME
       unlink - delete a name and possibly the file it refers to

SYNOPSIS
       #include <unistd.h>

       int unlink(const char *pathname);

DESCRIPTION
       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.

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 path-
	      name did not allow search (execute) permission.

       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.

       EPERM (Linux only)
	      The filesystem does not allow unlinking of files.

       EPERM  The system does not allow unlinking of directories, or unlinking of directories requires privileges that the current process doesn't
	      have.  (This is the POSIX prescribed error return.)

       EISDIR pathname refers to a directory.  (This is the non-POSIX value returned by Linux since 2.1.132.)

       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.

       ENAMETOOLONG
	      pathname was too long.

       ENOENT A component in pathname does not exist or is a dangling symbolic link, or pathname is empty.

       ENOTDIR
	      A component used as a directory in pathname is not, in fact, a directory.

       ENOMEM Insufficient kernel memory was available.

       EROFS  pathname refers to a file on a read-only filesystem.

       ELOOP  Too many symbolic links were encountered in translating pathname.

       EIO    An I/O error occurred.

CONFORMING TO
       SVr4, SVID, POSIX, X/OPEN, 4.3BSD.  SVr4 documents additional error conditions EINTR, EMULTIHOP, ETXTBSY, ENOLINK.

BUGS
       Infelicities in the protocol underlying NFS can cause the unexpected disappearance of files which are still being used.

SEE ALSO
       link(2), rename(2), open(2), rmdir(2), mknod(2), mkfifo(3), remove(3), rm(1)

Linux 2.0.30							    1997-08-21								 UNLINK(2)