sysvinit/man/fstab-decode.8

'\" -*- coding: UTF-8 -*-
.\" A man page for fstab-decode(8).
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.\" Author: Miloslav Trmac <mitr@redhat.com>
.TH fstab-decode 8 "May 2006"

.SH NAME
fstab-decode \- run a command with fstab-encoded arguments

.SH SYNOPSIS
\fBfstab-decode\fR \fICOMMAND\fR [\fIARGUMENT\fR]...

.SH DESCRIPTION
.B fstab-decode
decodes escapes (such as newline characters and other whitespace) 
in the specified \fIARGUMENT\fRs and uses them to run \fICOMMAND\fR.
The argument escaping uses the same rules as path escaping in
\fB/etc/fstab\fR,
.B /etc/mtab
and \fB/proc/mtab\fR.

In essence fstab-decode can be used anytime we want to pass multiple
parameters to a command as a list of command line argments. It turns output
like this:

.nf
/root
/mnt/remote-disk
/home

Into one long list of parameters, "/root /mnt/remote-disk /home". This
can be useful when trying to work with multiple filesystems at once. For
instance, we can use it to unmount multiple NFS shares. This program also
removes whitespace and other characters which might cause programs such
as mount or umount to fail.

.SH EXIT STATUS
.B fstab-decode
exits with status 127 if
.I COMMAND
can't be run.
Otherwise it exits with the status returned by \fICOMMAND\fR.

.SH EXAMPLES
.nf
The following example reads fstab, finds all instances of VFAT filesystems and
prints their mount points (argument 2 in the fstab file). fstab-decode then runs 
the specified program, umount, and passes it the list of VFAT mountpoints. 
This unmounts all VFAT partitions.


.B fstab-decode umount $(awk \[aq]$3 == \[dq]vfat\[dq] { print $2 }\[aq] /etc/fstab)
.fi