Consider using a config file and read the values within the child scripts, depending on whatever criteria you have to work with. If you have that many path variables it's worth thinking about this rather than managing then all within a series of scripts.

Marto, Could you please explain a little bit more about this as I am a beginner to this part of perl scripting. I don't have an idea about how to make config files and all ?? any help is appreciated . Thanks in advance!

Firstly, we're several posts into this thread and only found out that you have a requirement to deal with up to 20 different paths, with no mention of how you expect the correct paths to be passed to the 50 or so child scripts. What is your criteria for this? Ideally you'd have explained this in your initial post (I've asked you to read this a few times now). There are many ways to use config type files within perl, example.

"...I don't have an idea about how to make config files..."

Try Config::Tiny. And please see also Configuration file as well as INI file.

Regards, Karl

«The Crux of the Biscuit is the Apostrophe»

If the provided filenames differ between separate child scripts:

You can pass the filenames via command line and simply iterate over @ARGV to process them. If the length of the command is getting too long then you could provide the filenames by piping them into the childprocess via STDIN. Or you can write a temp file in the parent script and provide the child scripts with the filename to read from.

2 possibilities come to my mind at the moment:

If the file paths are not too long, you can pass them as additional parameters to system:

# master

my @files = qw[ path/to/file0 path/to/file1 path/to/file2 ];
system 'perl', 'slave.pl', @files;
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# slave

print "List of files to process:\n";
print "    $_\n" for (@ARGV);
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If the paths are too long to pass them all as parameters, write them to a file, 1 per line:

# master

my @files = qw[ path/to/file0 path/to/file1 path/to/file2 ];
open my $fh, '>', 'filelist';
print $fh, "$_\n" for (@files);
close $fh;
system 'perl', 'slave.pl'
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# slave

open my $fh, '<', 'filelist';
print "List of files to process:\n";
print while <$fh>;
close $fh;
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