#!/usr/bin/perl
# Usage: bootvars-subst subst0 value0 subst1 value1 ...
#                         < file > outfile

my %subst;
while (@ARGV) {
	my $key=shift;
	my $value=shift;
	$subst{$key}=$value;
}

while (<>) {
	s/\${BOOTPROMPT}\n?$//g; # special case
	s/\${([a-zA-Z0-9_]+)}/$subst{$1}/g;
	
	print;
}