Shell Programming and Scripting

My shell script generates a bunch of lines of text and passes this text as an argument to a perl script.

I'm able to do this, but for some reason newlines don't get recognized in the perl script and so the script just prints actual '\n' instead of carriage returning, otherwise everything gets passed just fine.

Not even sure what's causing this, but I'll settle for a solution.

Show us how are you passing that text to the Perl script.

Code:

if [ -n $notify ]
then
        ~/notify "$results"
fi

$results contains a bunch of lines delimited by newline characters

The perl script accesses it through $ARGV[0]

Basically the shell script accumulates a bunch of results, ships them off to the "mailman" perl script which in turn e-mails the results to a user.

Putting it in quotes causes it to pass it as one single argument. It's not perl that has to understand the newlines, it's the shell.

Keeping everything as one giant string like that is subject to limits, you know. On many systems you're not guaranteed anything more than 4 kilobytes of data in commandline arguments! If your data will ever be more than a page or so, you should be feeding the data into stdin instead of into arguments, as well as not storing it all in one giant variable inbetween, to prevent it being truncated when the data gets large. If you post your shell code we can show you how to adapt it, and on the perl side, you'd do something like:

Code:

while($line=<STDIN>)
{
        chomp($line);
        # do stuff with $line
}

and on the shell side, something like

Code:

while condition
do
       echo something
done | ~/notify

On some shells, you can kludge your existing solution like

Code:

OLDIFS="${IFS}"
IFS=$'\n'
~/notify $results
IFS="${OLDIFS}"

which will cause arguments to temporarily be split on newlines but not on other whitespace, splitting $results into arguments the way you want.