Bash Scripting help

jgtg32a · 09-04-2005, 11:18 PM

I have some experence coding in C++, Java but that was a HS class a few years ago, but we never did any work with external files so thats where I need help

Code:

#!/bin/bash
declare var ISO
function main
{
echo "Welcome to ISO tools"
echo ""
echo "1) Mount an Image"
echo "2) Unmount Image"
echo "3) Quit"
read var
if [ $var -eq "1" ] 
	then
	clear
	umount /mnt/iso #I got some wierd message about it being mounted multiple times so I added this
	echo "Select an ISO to mount" 
	#need to display the all the ISO locations and have them numbered so the number can be selected 
	read ISO
	if [ $ISO -eq "0" ]
		then 
		echo "enter the new ISO's path"
		read ISO
		echo $ISO >> iso.dat
	while [ $ISO -eq $var ]
		do
		# $ISO needs to be redefined as with its coorisponding location
		done
	fi
	mount -t iso9660 -o loop $ISO /mnt/iso 
elif [ $var -eq "2" ] 
	then
	umount /mnt/iso
elif [ $var -eq "3" ]
	then
	exit
else 
	clear
	main
fi
}
clear
main
exit

jschiwal · 09-05-2005, 12:46 AM

I don't know what you are trying to do with the "echo $ISO >> iso.dat" line.

However, for the part displaying and selecting iso file in a directory, try the select command:
select isofile in *.iso

bigearsbilly · 09-05-2005, 04:52 AM

as jschiwal said.

the select command will print numbered choices for you automatically.
Endlessly until you break
And you can use case which looks a bit neater than nested if statements
and uses globbing.

something like:

Code:

select file in  QUIT *.iso ;do
case $file in
   QUIT) break 2
   ;;

   *)   mount $file

esac
# break
done

jgtg32a · 09-05-2005, 09:20 PM

Well this will work

but I was hoping that I wouldn't have to hardcode all the iso locations, I was hoping to access them from a .dat so when I wanted to add a new ISO location I didn't have to modify the source code.

bigearsbilly · 09-06-2005, 08:33 AM

this is *nix
you don't have to do anything!

Code:

set -- `cat file.dat`

select file in $*

Is one way to skin this particular cat.

or

$LOCATIONS=`cat datfile`
select file in $LOCATIONS

and so on....
and so forth....

archtoad6 · 09-06-2005, 09:38 AM

0. Concur w/ billy.
Some other tips / suggestions.[list=1][*]What are you trying to do w/ declare var ISO?[*]function main is easier as main (), but then you may like to see "function".[*]Indent inside the function.[*]Keep the tab stops to 2, 3, or 4.[*]Fold the (expletive deleted) comment lines to fit on an 80 column screen.[/list=1]
Rick's 3 laws of programming: © f.a.archibald.iii 2003-2005
Clarity, Brevity, Generality.

The wide tab stops & esp. the long comment lines keep people from easily reading & grasping your code. Especially you, if you come back to it in, say, 6 months time. As a side effect it hoses the display of the entire thread on Konqueror -- it forces horizontal scrolling == PITA.

If you have any doubt about the idea of your future self as one of your most important readers, track down & read ESR's (Eric Raymond) piece on why he likes Python better than Perl.