Hello,

I'm trying to do a simple equivalent of 
grep -A1 -B1 'hello' file_name

[download]
in Perl. This basically prints the previous and the next line when the word 'hello' is found. I've done a super search and came up with the following links:

Grep - print matched line and next N lines
Emulating GNU grep -A and -B switches with perl

Both were created back in 2003 and I was wondering if there is now a more concise solution to this. I mean using the Linux 'grep' command, it is able to do it in one line which strikes me odd that it cannot be done in Perl in a concise manner.

Below is my code but again, I think it is too clunky and too long when compared to the Linux 'grep' command. 
#!/usr/bin/perl

use strict;

my ($prev, $next);
while (my $line = <DATA>) {
    if ( $next ) {
        print "$line";
        $next = undef;
    }
    if ( $line =~ /hello/ ) {
        print "$prev" if defined( $prev );
        print "$line";
        $next++;
    }
    $prev = $line;
}

__DATA__
test1
test2
hello
test3
test4

[download]
Thanks in advance.

In reply to Equivalent of Linux Grep Command by bichonfrise74

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