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mnttab(4)                      DG/UX 5.4R3.00                      mnttab(4)


NAME
       mnttab - mounted file system table

SYNOPSIS
       #include <mntent.h>

DESCRIPTION
       mnttab resides in the directory /etc and consists of a list of
       currently mounted file systems.  The file contains a number of lines
       like this:

            fsname dir type opts freq passno

       for example:

            /dev/dsk/usr  /usr  dg/ux  rw  1  1

       would indicate a mount for a local filesystem, and

            titan:/usr/titan  /usr/titan  nfs  rw,hard  0 0

       would indicate an NFS filesystem mount.  The entries from this file
       are accessed using the routines in getmntent(3C), which returns a
       structure of the following form:

       struct  mntent  {
          char   *mntfsname;   /* filesystem name */
          char   *mntdir;      /* filesystem path prefix */
          char   *mnttype;     /* dg/ux, nfs, swap, cdrom, or ignore */
          char   *mntopts;     /* rw, ro, hard, soft, fg, bg, memory */
          int    mntfreq;      /* highest dump level */
          int    mntpassno;    /* pass number on parallel fsck */
       };

       Fields are separated by white space; a #, as the first non-white
       character, indicates a comment.  The mnttype field determines how
       the mntfsname and mntopts fields will be interpreted.  The
       following is a list of the filesystem types currently supported, and
       the way each of them interprets these fields:


















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mnttab(4)                      DG/UX 5.4R3.00                      mnttab(4)


                 Type   Field       Interpretation

                 dg/ux  mnt_fsname  Must be a block special
                                    device.
                        mnt_opts    Valid options are ro, rw, bg,
                                    and fg.  If this has the
                                    ramdisk option, other options
                                    include use_wired_memory,
                                    max_file_space and
                                    max_file_count.

                 cdrom  mnt_fsname  Must be a block special
                                    device.

                 nfs    mnt_fsname  The hostname of the server and
                                    the pathname on the server of
                                    the directory to be served.  A
                                    colon separates the pathname
                                    and hostname.
                        mnt_opts    Valid options are ro, rw,
                                    hard, soft.

                 swap   mnt_fsname  Must be a block special device
                                    swap section.
                        mnt_opts    Ignored.


       If the mnttype is specified as ignore then the entry is ignored.
       This is useful to show disks not currently used.

       Entries identified as swap are made available as swap space by the
       swapon(1M) command at the end of the system reboot procedure.

       When the mntfsname field is interpreted as a block special device,
       programs that require the corresponding character special device must
       construct the name by changing dsk to rdsk in the pathname.

       If the mntopts field is a comma-separated list of options that
       includes ro or rw, then the filesystem is mounted read-write or read-
       only.  If this includes hard or soft, then the NFS filesystem is
       mounted hard or soft.

       The field mntfreq indicates how often each filesystem should be
       dumped by the dump(1M) command (and triggers that command's w option,
       which determines what filesystems should be dumped).  Most systems
       set the mntfreq field to 1, indicating that filesystems are dumped
       each day.

       The final field mntpassno is used by the consistency checking
       program fsck(1M) to allow overlapped checking of filesystems during a
       reboot.  All filesystems with a mntpassno of 1 are checked first
       simultaneously, then all filesystems with mntpassno of 2 are
       checked, and so on.  The <mntpassno> of the root filesystem should
       be 0, as the root cannot be checked since it is already mounted.



Licensed material--property of copyright holder(s)                         2




mnttab(4)                      DG/UX 5.4R3.00                      mnttab(4)


       The maximum number of entries in mnttab is based on the system
       parameter NMOUNT located in /usr/src/uts/mv/cf/config.h, which
       defines the number of allowable mounted special files.

SEE ALSO
       mount(1M), setmnt(1M).



















































Licensed material--property of copyright holder(s)                         3


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