Hi,

I'm playing around with bash scripting to get some kind of a backup script operational.
The script has to read some parameters from a configuration file, ofcourse not taking into account the commented lines.
I came up with the following:

config file (backup.conf)
------------------------------
# configuration backupscript
# I have noticed that putting the backupscript in a directory that has to be backupped causes the backup to fail.
#
# backupdir: where the backupped files will be saved
backupdir=/mnt/hdb/bu
#
# errorlog: what file will contain the logs
errolog=/mnt/hdb/bu/error.log
#
# backuplist: the file that will contain the directories to be backupped
backuplist=/mnt/hdb/backupscripts/backup.list
#


readfile script (test.sh)
-----------------------------
#!/bin/bash
# read a file line by line

file=/mnt/hdb/backupscripts/backup.conf

x=0

#wc returns for some reason also the name of the file, I only need the amount of lines:
lns=`wc -l $file`
y=`expr "$lns" : '\([0-9]*\)'`

#read the file, line by line using a head-tail trick:
while [ "$x" -lt "$y" ]
do
let x=x+1
#read the line
line=`head -n $x $file | tail -n 1`
#remove all whitespaces because otherwise, expr substr will complain
#(because it sees each word in $line as a different variable I think)
word=`echo $line | sed -e 's/ //g'`
#finally get the first character
char=`expr substr $word 1 1`
#print the line if it doesn't start with a '#'
if [ "$char" != "#" ]
then
echo $line
fi
done

exit 0


This works fine for now but it seems rather complicated for such a simple task. Can anyone point me to a more elegant solution?
How can I make 'expr substr $var' think that the $var is only one variable, even it it contains whitespaces?

btw; I made the script while looking in tutorials etc. So my knowledge regarding regular expressions is very low.

thanks,
Lieven

If you trust the configuration file (it is writable only by root), then you can just use the following one-liner in your script:

. /etc/backup.conf

The leading period and space will cause the contents of the file to be included in the current shell environment.

So if I just do . /etc/backup.conf then that file will be included as a part of the script and everything in it will be considered a part of the script.
Because the config file is indeed only writable by root, I think I will do it like that.
Thanks for the reply.