Shell Programming and Scripting

Thanks kpearson, I think I see the problem. The thing is as I am in effect opening a file from read variable so that I can work my program on it, I can't modify variable because my program won't be able to take it in. E.g. a file might be called "file 1" and so removing the space would change the filename to something that doesn't exist.

Therefore I just want to leave a condition preventing names like "file 1" from being entered. This would prevent any malfunction in my program. I have tried what you have written at the bottom. I noticed one of your back quotes are missing. Did u mean:

Code:

CHK=`echo $filename|cut -f2 -d' '`
if [ "$CHK" -ne " " ] ; then
        echo "Multiple filenames entered."
        exit
fi

where filename is the line input.

Yes, 2 backtics are necessary. Sorry.

You should remember about the following:
1. Always use " or ' for strings/parameters when you use them as value
2. Always use {} for variables - it helps to avoid problems like:
echo $10

If you are using filenames passed as command line params you could probably use the following (this is a simplified form that removes the list after use):
while [[ $# -gt 0 ]] ;do
do something on ${1}
shift
done

Hi guys thanks for the help.. I think I have sorted it now using a pattern matching condition which looks for " " (spaces) and if any are present from the user input, an error is returned and the file is exited.

I thought there would be a pre-defined condition for this file scenario and that's why I asked about it.

Thanks for the reminder adderek. Can I ask you a quick question.

What does this do:

Code:

 function "$variable1" $variable2

Does the double quotes tell function to treat $variable1 as a string variable? I.e take in all the text in it as one value?

function "$variable1" $variable2
This tells that there is at least 1 parameter and $variable2 can contain parameters 2-d and other.

Some example written ad-hoc (on files ):

Code:

#!/bin/ksh
function print_filenames {
while [[ $# -gt 0 ]] ;do
print "Filename: <${1}>"
shift 1
done
return 0
}
print_filenames "/home/user/First filename within $HOME.txt" '/home/user/Second filename within $HOME.txt' /home/user/Third filename within $HOME.txt

Output:

Filename: </home/user/First filename within /home/user.txt>
Filename: </home/user/Second filename within $HOME.txt>
Filename: </home/user/Third>
Filename: <filename>
Filename: <within>
Filename: </home/user.txt>

Ah I wasn't sure what you meant by "parameters 2-d" but your example illustrated it perfectly . My hats off to you.. that one is definitely going in my private notes . Thanks a lot

CJ

And thanks for adding

Code:

shift

which I haven't used much and had forgotten about.

Nice touch.