unlink.2

操作系统设计与实现源码

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


NAME
     unlink - remove directory entry

SYNOPSIS
     #include <unistd.h>

     int unlink(const char *path)

DESCRIPTION
     Unlink removes the entry for the file path from its directory.   If  this
     entry  was  the  last link to the file, and no process has the file open,
     then all resources associated with the file are reclaimed.  If,  however,
     the  file  was  open  in  any process, the actual resource reclamation is
     delayed  until  it  is  closed,  even  though  the  directory  entry  has
     disappeared.

RETURN VALUE
     Upon successful completion, a value of 0 is returned.  Otherwise, a value
     of -1 is returned and errno is set to indicate the error.

ERRORS
     The unlink succeeds unless:

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

     [ENAMETOOLONG] The path name exceeds PATH_MAX characters.

     [ENOENT]       The named file does not exist.

     [EACCES]       Search permission is denied for a component  of  the  path
                    prefix.

     [EACCES]       Write permission is denied on the directory containing the
                    link to be removed.

     [ELOOP]        Too many symbolic links were  encountered  in  translating
                    the pathname.  (Minix-vmd)

     [EPERM]        The named file is a directory.

     [EPERM]        The directory containing the file is  marked  sticky,  and
                    neither  the  containing  directory  nor  the  file  to be
                    removed are owned by the effective user ID.  (Minix-vmd)

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

     [EIO]          An I/O error occurred while deleting the  directory  entry
                    or deallocating the inode.



4BSD                              May 22, 1985                               1



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


     [EROFS]        The named file resides on a read-only file system.

     [EFAULT]       Path points outside the process's allocated address space.

SEE ALSO
     close(2), link(2), rmdir(2).














































4BSD                              May 22, 1985                               2