How to match once per file in grep?

Question

Is there any grep option that let\'s me control total number of matches but stops at first match on each file?

Example:

If I do this grep -ri --include \'*

Answer 1

You can do this easily in perl, and no messy cross platform issues!

use strict;
use warnings;
use autodie;

my $match = shift;

# Compile the match so it will run faster
my $match_re = qr{$match};

FILES: for my $file (@ARGV) {
    open my $fh, "<", $file;

    FILE: while(my $line = <$fh>) {
        chomp $line;

        if( $line =~ $match_re ) {
            print "$file: $line\n";
            last FILE;
        }
    }
}

The only difference is you have to use Perl style regular expressions instead of GNU style. They're not much different.

You can do the recursive part in Perl using File::Find, or use find feed it files.

find /some/path -name '*.coffee' -print0 | xargs -0 perl /path/to/your/program