#!/usr/bin/perl -s

our($fs);
$fs ||= ":";

$f1 = shift;
$cond = shift;

$b = `head -1 $f1`;
chomp $b;

for (split(/\s*$fs\s*/,$b)){ $corr{$_} = ++$n }

$cond =~ s/\$([#\w]+)/'$'.($corr{$1}||die("Error: $1 not found\n"))/eg;

$com ="awk 'BEGIN {OFS=FS=\"$fs\"} NR==1||($cond){print \$0}' $f1";

system "$com";