Re: Search and replace on a 130000+ line file.

in reply to Search and replace on a 130000+ line file.

Here is my quick and nasty solution. This loads the first file into a hash so it may use up lots of memory. Though if it too is 130,000 lines that is only a few megabytes.

Should run fast! (Tested also ;-)

use strict;
die "Syntax: $0 <names> < djb-file > output-file" unless @ARGV == 1;
my %name_to_ip;
open(IN, "<".shift) or die;
while (<IN>)
{
    chomp;
    my ($ip, $name) = split /:/;
    $name_to_ip{$ip} = $name;
}
close IN or die;

while (<>)
{
    chomp;
    my ($name, $ip) = split /:/;
    print $name_to_ip{$ip} || $name, ":", $ip, "\n";
}
[download]

Comment on Re: Search and replace on a 130000+ line file. Download Code

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Re: Re: Search and replace on a 130000+ line file. by sierrathedog04 (Hermit) on May 11, 2001 at 23:05 UTC
For whatever reason, the line: `open(IN, "<".shift) or die;` [download] doesn't work for me in ActiveState Perl 5.6 /NT workstation when I call the above program as `perl tempo.pl ip.dat djb.dat` [download] However, the program works great when I replace that line with: `open(IN, "<ip.dat") or die;` [download] and call it as: `perl tempo.pl djb.dat` [download]	[reply] [d/l] [select]

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