UNLINK(2-SVR4)      RISC/os Reference Manual       UNLINK(2-SVR4)



NAME
     unlink - remove directory entry

SYNOPSIS
     #include <unistd.h>

     int unlink(const char *path);

DESCRIPTION
     unlink removes the directory entry named by the path name
     pointed to by path.  and decrements the link count of the
     file referenced by the directory entry.  When all links to a
     file have been removed and no process has the file open, the
     space occupied by the file is freed and the file ceases to
     exist.  If one or more processes have the file open when the
     last link is removed, space occupied by the file is not
     released until all references to the file have been closed.
     If path is a symbolic link, the symbolic link is removed.
     path should not name a directory unless the process has
     appropriate privileges.  Applications should use rmdir(2) to
     remove directories.

     Upon successful completion unlink marks for update the
     st_ctime and st_mtime fields of the parent directory. Also,
     if the file's link count is not zero, the st_ctime field of
     the file is marked for update.

     The named file is unlinked unless one or more of the follow-
     ing are true:

     EACCES              Search permission is denied for a com-
                         ponent of the path prefix.

     EACCES              Write permission is denied on the direc-
                         tory containing the link to be removed.

     EACCES              The parent directory has the sticky bit
                         set and the file is not writable by the
                         user; the user does not own the parent
                         directory and the user does not own the
                         file;

     EBUSY               The entry to be unlinked is the mount
                         point for a mounted file system.

     EFAULT              path points outside the process's allo-
                         cated address space.

     EINTR               A signal was caught during the unlink
                         system call.

     ELOOP               Too many symbolic links were encountered



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UNLINK(2-SVR4)      RISC/os Reference Manual       UNLINK(2-SVR4)



                         in translating path.

     EMULTIHOP           Components of path require hopping to
                         multiple remote machines and the file
                         system does not allow it.

     ENAMETOOLONG        The length of the path argument exceeds
                         {PATH_MAX}, or the length of a path com-
                         ponent exceeds {NAME_MAX} while
                         _POSIX_NO_TRUNC is in effect.

     ENOENT              The named file does not exist or is a
                         null pathname.  The user is not a
                         superuser.

     ENOTDIR             A component of the path prefix is not a
                         directory.

     EPERM               The named file is a directory and the
                         effective user ID of the process is not
                         superuser.

     ETXTBSY             The entry to be unlinked is the last
                         link to a pure procedure (shared text)
                         file that is being executed.

     EROFS               The directory entry to be unlinked is
                         part of a read-only file system.

     ENOLINK             path points to a remote machine and the
                         link to that machine is no longer
                         active.

SEE ALSO
     close(2), link(2), open(2), rmdir(2).
     rm(1) in the User's Reference Manual.

DIAGNOSTICS
     Upon successful completion, a value of 0 is returned.  Oth-
     erwise, a value of -1 is returned and errno is set to indi-
     cate the error.














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