Re: [Boston.pm] grep w/ 'context'

[John Abreau]

Ron Newman <[EMAIL PROTECTED]> writes:

> But this won't solve the original problem, which was how to write a
> Perl script that provides N lines of context before and after a 'grep' match.
> Your program processes each line one at a time, and doesn't store a
> buffer of lines. 

Try this:

    my $N = 10;
    my $regex = shift;
    my @buffer = ();

    while (<>) {
        push(@buffer, $_);
        next if $. < $N * 2;
        if ($buffer[$N] =~ /$regex/) {
            print "@buffer\n";
        }
    }

Adjust the print statement to taste.  :-)


-- 
John Abreau / Executive Director, Boston Linux & Unix 
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