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File for predefined mountpoints




The /etc/fstab file contains descriptive information about filesystems. Programs read it, but don't write it; it's the duty of the system administrator to properly create and maintain this file. Each filesystem is described on a separate line; fields on each line are separated by tabs or spaces. Lines beginning with # are comments.

If you specify the -a option to the mount command, the utility mounts the devices that are listed in /etc/fstab. The format of the /etc/fstab used with the mount utility is as follows:

specialdevice mountpoint type mountoptions

For example, the following entry in /etc/fstab:

/dev/hd0t77 /mnt/fs qnx4 rw

is equivalent to calling:

mount -t qnx4 /dev/hd0t77 /mnt/fs

The mountoptions field is a comma-separated list of values that must contain, at a minimum, one of ro or rw to indicate a read-only or a read-write mount.

By default, the mount is performed with the type as if the -t option had been specified (device and server doing the mount are the same) but to get the -T type behavior, you should specify allservers in the options.

The following sample /etc/fstab indicates the mapping of the different configurations:

#This is a sample file that shows the mapping of command line
#arguments to the fstab entries and how they would be invoked.
#The "implied" argument is not generally required, but some
#servers may differentiate between implied and specified entries.

# mount -b -vvv -t mytype /my/specialdev1 /my/mountpoint1
# mount -vvv /my/mountpoint1
/my/specialdev1 /my/mountpoint1 mytype rw

# mount -b -vvv -t mytype /my/specialdev2
# mount -vvv /my/specialdev2
/my/specialdev2 / mytype rw,implied

# mount -b -vvv -T mytype /my/specialdev3 /my/mountpoint3
# mount -vvv /my/mountpoint3
/my/specialdev3 /my/mountpoint3 mytype allservers,rw

# mount -b -vvv -T mytype /my/specialdev4
# mount -vvv /my/specialdev4
/my/specialdev4 / mytype allservers,implied,rw

See also:


endfsent(), getfsent(), getfsfile(), getfsspec(), mount(), setfsent() in the QNX Neutrino Library Reference