umount(3)                                               umount(3)



NAME
     umount - unmounts a file system

SYNOPSIS
     int umount(spec)
     char *spec;

DESCRIPTION
     umount requests that a previously mounted file system
     contained on the block special device identified by spec be
     unmounted.  spec is a pointer to a path name.  After
     unmounting the file system, the directory upon which the
     file system was mounted reverts to its ordinary
     interpretation.

     umount may be invoked only by the superuser.

STATUS MESSAGES AND VALUES
     Upon successful completion, a value of 0 is returned.
     Otherwise, a value of -1 is returned and errno is set to
     indicate the error.

     The umount program will fail if one or more of the following
     are true:

     EPERM
          The process's effective user ID is not superuser.

     ENXIO
          spec does not exist.

     ENOTBLK
          spec is not a block special device.

     EINVAL
          spec is not mounted.

     EBUSY
          A file on spec is busy.

     EFAULT
          spec points to an illegal address.

SEE ALSO
     fsmount(2), unmount(2), mount(3)










January 1992                                                    1