Hi there!

So, I have a while -loop. And I stay in this loop unill I have reached the end of the file (result.txt). This file is the output of the "tree" command.

Now is my question: is it possible to directly insert the lines of the "tree" command in the loop, so I can skip the making of a file. Probably it has something to do with the line "done < result.txt"

Thanks for helping..


function overvieuwFunction {
while read line;
do
echo "${line}";
done < result.txt;
}

PROJECTDIR=`pwd`;
cd /;
rm $PROJECTDIR/result.txt;
tree -if -P "*.conf" $PROJECTDIR > $PROJECTDIR/result.txt;
cd $PROJECTDIR;

overvieuwFunction;

You can skip the redirection to a file piping the output of the tree command directly to the while loop:

Thanks, but this I have already tried. This works, but is not what I am searching. I don't know how to explain it well, but I will do it by example: I use this kind of code:



function countFunction {
while read line;
do
let $1=400;
done < result.txt;
}

LVAR=0;
countFunction LVAR;



And using the pipe, like in your example, makes that "let $1=400" does not work. Beceause, it has something to do that a pipe opens a new enviroment, so by doing this, the reference to LVAR (with the $1) is gone!

I hope you can follow :-)

So I realy have to find a solution for "done < result.txt" :-)

Sorry and greetings!

I couldn't find a way to make bash do what you wanted without using a file in one way or another.

If you don't mind using a more traditional shell, ksh doesn't suffer from that 'pipelines in a subshell' nonsense that can be so annoying in bash.

By the way, passing the variable name into the function via $1 and then substituting that on the lefthand side of the assignment within the function is not a technique I've seen before and it's a little on the ugly side. It's not something I'd recommend doing if you can avoid it. It took me a good couple of minutes just to figure out what you were up to there.

Anyway, hope this was of some use to you.

I got the point. In bash an alternative is process substitution. It does not open a subshell as the pipe does and let you to use the output of a process (or multiple processes) as input to another process. For example:
In this way every variable assigned within the while loop is kept outside.

D'oh! I looked at process substitution, but as it substitutes to a filename I couldn't see how to use it on a while/done. It never occurred to me that it could be used with a redirection operator. (Well, it was about 1am in the morning!... Er, yeah, that excuse might fly! )

Nice one colucix, you've taught me something again.

Yes, thanks, that was what I was searching!

Thanks a lot! Greetings from little cold Belgium!