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NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | VERSIONS | CONFORMING TO | NOTES | SEE ALSO | COLOPHONThe Linux Programming Interface

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

NAME         top

       unlinkat  -  remove  a  directory  entry relative to a directory file
       descriptor

SYNOPSIS         top

       #include <fcntl.h> /* Definition of AT_* constants */
       #include <unistd.h>

       int unlinkat(int dirfd, const char *pathname, int flags);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       unlinkat():
           Since glibc 2.10:
               _XOPEN_SOURCE >= 700 || _POSIX_C_SOURCE >= 200809L
           Before glibc 2.10:
               _ATFILE_SOURCE

DESCRIPTION         top

       The unlinkat() system call operates in exactly the same way as either
       unlink(2) or rmdir(2) (depending on whether or not flags includes the
       AT_REMOVEDIR flag) except for the differences described in this
       manual page.

       If the pathname given in pathname is relative, then it is interpreted
       relative to the directory referred to by the file descriptor dirfd
       (rather than relative to the current working directory of the calling
       process, as is done by unlink(2) and rmdir(2) for a relative
       pathname).

       If the pathname given in pathname is relative and dirfd is the
       special value AT_FDCWD, then pathname is interpreted relative to the
       current working directory of the calling process (like unlink(2) and
       rmdir(2)).

       If the pathname given in pathname is absolute, then dirfd is ignored.

       flags is a bit mask that can either be specified as 0, or by ORing
       together flag values that control the operation of unlinkat().
       Currently only one such flag is defined:

       AT_REMOVEDIR
              By default, unlinkat() performs the equivalent of unlink(2) on
              pathname.  If the AT_REMOVEDIR flag is specified, then
              performs the equivalent of rmdir(2) on pathname.

RETURN VALUE         top

       On success, unlinkat() returns 0.  On error, -1 is returned and errno
       is set to indicate the error.

ERRORS         top

       The same errors that occur for unlink(2) and rmdir(2) can also occur
       for unlinkat().  The following additional errors can occur for
       unlinkat():

       EBADF  dirfd is not a valid file descriptor.

       EINVAL An invalid flag value was specified in flags.

       ENOTDIR
              pathname is relative and dirfd is a file descriptor referring
              to a file other than a directory.

VERSIONS         top

       unlinkat() was added to Linux in kernel 2.6.16; library support was
       added to glibc in version 2.4.

CONFORMING TO         top

       POSIX.1-2008.  A similar system call exists on Solaris.

NOTES         top

       See openat(2) for an explanation of the need for unlinkat().

SEE ALSO         top

       openat(2), rmdir(2), unlink(2), path_resolution(7)

COLOPHON         top

       This page is part of release 3.51 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                            2012-05-04                      UNLINKAT(2)

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