Obligatory Tie::File solution. I haven't done any benchmarks, but I would guess it's as fast as the other Perl solutions while being less memory-intensive.
As others have said, /bin/grep is the way to go here.
#!/usr/bin/perl
use strict;
use warnings;
use Tie::File;
use Fcntl 'O_RDONLY';
my $DEBUG = 0;
my $text = qr/c9391b56-b174-441b-921c-7d63/;
my $file = 'GWSvc.log';
my $context = 3;
sub dprint { print @_ if $DEBUG };
my @lines;
tie @lines, 'Tie::File', $file, mode => O_RDONLY
or die "tie failed: $!";
for (my $i = 0; $i <= $#lines; $i++) {
dprint "SCAN: line $i\n";
if ($lines[$i] =~ /$text/) {
dprint "MATCH at line $i\n";
my $start = $i - $context;
if ($start < 0) {
$start = 0;
};
my $end = $i + $context;
for my $j ($start .. $end) {
dprint "$j: ";
print "$lines[$j]\n";
};
print "\n";
$i += $context;
};
};
-
Are you posting in the right place? Check out Where do I post X? to know for sure.
-
Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
<code> <a> <b> <big>
<blockquote> <br /> <dd>
<dl> <dt> <em> <font>
<h1> <h2> <h3> <h4>
<h5> <h6> <hr /> <i>
<li> <nbsp> <ol> <p>
<small> <strike> <strong>
<sub> <sup> <table>
<td> <th> <tr> <tt>
<u> <ul>
-
Snippets of code should be wrapped in
<code> tags not
<pre> tags. In fact, <pre>
tags should generally be avoided. If they must
be used, extreme care should be
taken to ensure that their contents do not
have long lines (<70 chars), in order to prevent
horizontal scrolling (and possible janitor
intervention).
-
Want more info? How to link
or How to display code and escape characters
are good places to start.
|