Is this really what you want to do?

Is the script you're calling big and unchangeable? If it's only a small one wouldn't it be better to include its code into your script?

If it's a big one, can you clone it and make a copy that's got this loop around its functionality?

If you're running an external command using backticks `` like that - firstly as sk pointed out you have put the filename outside the backticks, so it won't be provided as an argument to the script you're running, but I wouldn't recommend using backticks in the first place.

If you really must shell out to an external program you're better to use: 

system("...") && die "Can't run ...: $!\n";

[download]
or 
system("...") == 0 || die "Can't run '...' [$?]: $!\n"

[download]
or 
open("... |") || die "Can't run ...: $1\n";

[download]
if you want the output from it - this way the operating system is going to report back to your script whether the program you shelled out to returned an error or a success.

`` is easy to use but generally sloppy in that it says something like "go away and try and run this, I don't really care if it works or not, but just give me back whatever came back from STDOUT (I don't care about STDERR either)" - which probably isn't what you want your program to do!

Update:

Thanks sauoq for pointing out the obvious mistake - NB system() unlike open() returns the output of the program that you ran modified by some rules (which sauoq has expanded below)

Sorry I rushed out my answer as I was racing out the door running late for a conference!

In reply to Re: calling a perl script within a perl script by serf
in thread calling a perl script within a perl script by sbp

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