umount(2)                                                         umount(2)


   NAME
         umount - unmount a file system

   SYNOPSIS
         #include <sys/mount.h>

         int umount(const char *file);

   DESCRIPTION
         umount requests that a previously mounted file system contained on
         the block special device or directory identified by file be
         unmounted.  file 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 super-user.

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

         EPERM               The process's effective user ID is not super-
                             user.

         EINVAL              file does not exist.

         ELOOP               Too many symbolic links were encountered in
                             translating the path pointed to by file.

         ENAMETOOLONG        The length of the file argument exceeds
                             {PATHMAX}, or the length of a file component
                             exceeds {NAMEMAX} while POSIXNOTRUNC is in
                             effect.

         ENOTBLK             file is not a block special device.

         EINVAL              file is not mounted.

         EBUSY               A file on file is busy.

         EFAULT              file points to an illegal address.

         EREMOTE             file is remote.

         ENOLINK             file is on a remote machine, and the link to that
                             machine is no longer active.

         EMULTIHOP           Components of the path pointed to by file require
                             hopping to multiple remote machines.

   SEE ALSO
         mount(2).



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   umount(2)                                                         umount(2)


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


















































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