epaste

#!/usr/bin/env perl
use strict;
no strict 'refs';

my ($VERSION) = '$Revision: 1.2 $' =~ /([.\d]+)/;

my (@fh, $i);

my @sep = ( "\t" );
my $dash_ess = 0;

exit if not @ARGV;

while ($ARGV[0] =~ /^-[^=]+$/) {
	$_ = shift @ARGV;
	/^-\?$/ and do { print <<EOF;
Usage: $0 [-s] [-d list] file...

Merges the corresponding lines of files.
EOF
		exit;
	};
	/^-d$/ and do { 
		my $arg = shift;
		@sep = split(//, eval qq{sprintf("$arg")}); 
		next;
	};
	/^-s$/ and do { $dash_ess = 1; next; }
}

for $i (0..$#ARGV) {
	$fh[$i] = "F$i";
	my( $name, $line ) = $ARGV[$i] =~ /(.*?) (?: = ([0-9]+) )? \z/x;
	print "$fh[$i] $name $line\n";
	open($fh[$i], $name) or die "$0: cannot open $name";
	if( defined $line ) {
		tell( $fh[$i] );
		readline( $fh[$i] ) while $. < $line - 1
	}
}

if ($dash_ess) {
	foreach $i (0..$#fh) {
		my $fh;
		$fh = $fh[$i];
		my $current_sep = 0;
		my $tline;
		while(<$fh>) { 
			chomp; 
			$tline .= $_ . $sep[$current_sep++];
			$current_sep = 0 if $current_sep == scalar @sep;
		}
		print "$tline\n";
		close $fh;
	}
	exit;
}

my $files_still_open = 1;
while (1) {
	my $current_sep = 0;
	$files_still_open = 0;
	foreach $i (0..$#fh) {
		$files_still_open = 1 if not eof $fh[$i];
	}
	last if not $files_still_open;

	my $tline;
	foreach $i (0..$#fh) {
		if (not eof $fh[$i]) {
			my $fh;
			$fh = $fh[$i];
			my $line = <$fh>;
			chomp($line);
			$tline .= $line;
		}
		$tline .= "$sep[$current_sep++]" if $i != $#fh;
		$current_sep = 0 if $current_sep == scalar @sep;
	}
	print "$tline\n";
}