#! /usr/bin/perl -w use strict; use warnings; # a wrapper for head for use in galaxy # headWrapper.pl [filename] [# lines to show] [output] die "Check arguments" unless @ARGV == 3; die "Line number must be an integer\n" unless $ARGV[1]=~ m/^\d+$/; open (OUT, ">$ARGV[2]") or die "Cannot create $ARGV[2]:$!\n"; open (HEAD, "head -n $ARGV[1] $ARGV[0]|") or die "Cannot run head:$!\n"; while () { print OUT; } close OUT; close HEAD;