#!/home/ben/software/install/bin/perl
use warnings;
use strict;
use utf8;
use File::Slurper 'read_text';
use Text::LineNumber;
my $file = "test.c";
my $c = read_text ($file);
my $tln = Text::LineNumber->new ($c);
while ($c =~ /\b(bsearch[^;]*);/g) {
    my $match = $1;
    my $pos = pos ($c) - length ($match);
    my $line = $tln->off2lnr ($pos);
    print "$file:$line: '$match'.\n";
}