#!/usr/bin/perl

# An Unicode-aware grep. It searches patterns in UTF-8 encoded files.
# Of course, it is far from having all the options of GNU grep...

$pattern = $ARGV[0];
if (! $pattern) {
    die "Usage: $0 pattern file ..."
    }
if (! $ARGV[1]) {
    binmode STDIN, ":utf8";
    while (<STDIN>) {
	if (/$pattern/) { 
	    print $_;
	}
    }
}
else {
    if ($ARGV[2]) {
	$multiple = 1;
    }
    else {
	$multiple = 0;
    }
    shift @ARGV;
    for $file (@ARGV) {
	open(FILE, "<:utf8", $file) or die "Cannot open $file: $!";
	while (<FILE>) {
	    if (/$pattern/) { 
		if ($multiple) {
		    print $file, ": ";
		}
		print $_;
	    }
	}
    }
}