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NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | CONFORMING TO | BUGS | SEE ALSO | COLOPHON


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

NAME         top

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

SYNOPSIS         top

       #include <unistd.h>

       int unlink(const char *pathname);

DESCRIPTION         top

       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         top

       On success, zero is returned.  On error, -1 is returned, and errno is set
       appropriately.

ERRORS         top

       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         top

       SVr4, 4.3BSD, POSIX.1-2001.

BUGS         top

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

SEE ALSO         top

       rm(1), chmod(2), link(2), mknod(2), open(2), rename(2), rmdir(2), unlinkat(2),
       mkfifo(3), remove(3), path_resolution(7), symlink(7)

COLOPHON         top

       This page is part of release 3.23 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/.

Linux                                 2004-06-23                            UNLINK(2)