Take a look at the man pages for system and backticks ``

Backticks are useful if you want to capture the output of the external program.

my $output = `/home/mailman/bin/add_members -n/home/mailman/lists/minl
+ist-news/email.out -wy minlist-news` or die "Cant' add members: $!\n"
+;
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The or die part is important -- it will be called if something goes wrong with the external program.

An alternative to backticks is system, just system "command", which is more useful when you don't need to capture the output and/or when you want more security (it's dangerous to put user input into any call that's going to get executed on your system).

HTH!

perl -e 'print "How sweet does a rose smell? "; chomp ($n = <STDIN>); 
+$rose = "smells sweet to degree $n"; *other_name = *rose; print "$oth
+er_name\n"'
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