System Calls                                            unlink(2)



NAME
     unlink - remove directory entry

SYNOPSIS
     #include <unistd.h>

     int unlink(const char *path);

DESCRIPTION
     The unlink() function removes a link  to  a  file.  If  _p_a_t_h
     names  a  symbolic  link, unlink() removes the symbolic link
     named by _p_a_t_h and does not  affect  any  file  or  directory
     named  by  the  contents  of  the symbolic link.  Otherwise,
     unlink() removes the link named by the pathname  pointed  to
     by _p_a_t_h and decrements the link count of the file referenced
     by the link.

     When the file's link count becomes 0 and no process has  the
     file  open, the space occupied by the file will be freed and
     the file will no  longer  be  accessible.  If  one  or  more
     processes  have the file open when the last link is removed,
     the link will be removed before unlink()  returns,  but  the
     removal  of  the  file  contents will be postponed until all
     references to the file are closed.

     The _p_a_t_h argument must not name a directory unless the  pro-
     cess  has appropriate privileges and the implementation sup-
     ports using unlink() on directories.

     Upon successful completion, unlink() will  mark  for  update
     the  st_ctime  and  st_mtime fields of the parent directory.
     If the file's link count is not 0, the st_ctime field of the
     file will be marked for update.

RETURN VALUES
     Upon successful completion, 0 is returned.  Otherwise, -1 is
     returned,  errno  is set to indicate the error, and the file
     is not unlinked.

ERRORS
     The unlink() function will fail if:

     EACCES
           Search permission is denied for  a  component  of  the
           _p_a_t_h  prefix; write permission is denied on the direc-
           tory containing the link to  be  removed;  the  parent
           directory  has  the sticky bit set and the file is not
           writable by the user; or 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.



SunOS 5.8           Last change: 28 Dec 1996                    1






System Calls                                            unlink(2)



     EFAULT
           The _p_a_t_h argument points to an illegal address.

     EINTR A signal  was  caught  during  the  execution  of  the
           unlink() function.

     ELOOP Too many symbolic links were encountered in  translat-
           ing _p_a_t_h.

     ENAMETOOLONG
           The length of the _p_a_t_h argument exceeds  _P_A_T_H__M_A_X,  or
           the  length of a _p_a_t_h component exceeds _N_A_M_E__M_A_X while
           _POSIX_NO_TRUNC is in effect.

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

     ENOLINK
           The _p_a_t_h argument points to a remote machine  and  the
           link to that machine is no longer active.

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

     EPERM The named file is a directory and the  effective  user
           of the calling process is not super-user.

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

     The unlink() function may fail if:

     ENAMETOOLONG
           Pathname resolution of a  symbolic  link  produced  an
           intermediate result whose length exceeds _P_A_T_H__M_A_X.

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

USAGE
     Applications should use rmdir(2) to remove a directory.

ATTRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:








SunOS 5.8           Last change: 28 Dec 1996                    2






System Calls                                            unlink(2)



     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |______________________________|______________________________|
    | MT-Level                    | Async-Signal-Safe           |
    |______________________________|______________________________|


SEE ALSO
     rm(1), close(2),  link(2),  open(2),  rmdir(2),  remove(3C),
     attributes(5)













































SunOS 5.8           Last change: 28 Dec 1996                    3