unlink(2)                        DG/UX 5.4.2                       unlink(2)


NAME
       unlink - remove a directory entry

SYNOPSIS
       #include <unistd.h>
       int  unlink (path)
       char * path;

   where:
       path      Address of a pathname

DESCRIPTION
       Unlink removes the directory entry named by the pathname pointed to
       by path from the filename store.  A symbolic link occurring at the
       end of path will not be followed.  The named file must reside on a
       file system device mounted read-write.

       The subject file must be of type `ordinary-disk-file', `block-
       special-file', `character-special-file', `fifo-special-file',
       `socket', or `symbolic-link'.

       It is an error to attempt an unlink call on a directory or control
       point directory type file.

       Removing a reference to a file in the filename store has the
       following consequences:

       ⊕      The subject file's link count attribute is decremented.

       ⊕      The subject file's `time-last-attribute-changed' attribute is
              set to the current time.

       ⊕      If the subject file has no more links in the filename store,
              then on the release of the last reference, the file will
              removed from the flat file store.  Thus, unlink deletes
              inactive files.

       ⊕      If the subject file has no more links in the filename store
              but is still open, then the file is removed from the
              filesystem when it is closed for the last time.

       If unlink fails, no changes are made to the named file.

ACCESS CONTROL
       The calling process must have permission to resolve path.

       The calling process must have write permission to the directory
       containing the entry to be removed.

RETURN VALUE
       0      The filename was successfully removed.

       -1     An error occurred.  errno is set to indicate the error.




Licensed material--property of copyright holder(s)                         1

unlink(2)                        DG/UX 5.4.2                       unlink(2)


DIAGNOSTICS
       Errno may be set to one of the following error codes:

       EACCES         Permission to modify the directory containing the
                      entry to be removed is denied to the calling process.

       EBUSY          The named file is the mount point of a file system
                      device.

       EPERM          The named file is a directory.

       EROFS          The named file is contained on a read-only file system
                      device.

       ENOENT         The file the pathname resolved to does not exist.

       ENOENT         A non-terminal component of the pathname does not
                      exist.

       ENOTDIR        A non-terminal component of the pathname was not a
                      directory or symbolic link.

       ENAMETOOLONG   The pathname exceeds the length limit for pathnames.

       ENAMETOOLONG   A component of the pathname exceeds the length limit
                      for filenames.

       ENOMEM         There are not enough system resources to resolve the
                      pathname or to expand a symbolic link.

       ELOOP          The number of symbolic links encountered during
                      pathname resolution exceeded MAXSYMLINKS.  A symbolic
                      link cycle is suspected.

       EPERM          The pathname contains a character not in the allowed
                      character set.

       EFAULT         The pathname does not completely reside in the
                      process's address space or the pathname does not
                      terminate in the process's address space.

SEE ALSO
       rm(1), close(2), link(2), open(2).














Licensed material--property of copyright holder(s)                         2