One liner help

VinsWorldcom has asked for the wisdom of the Perl Monks concerning the following question:

I have a DNS zone file that I parsed to just the network addresses. They look like this:

1.100.10
2.100.10
3.100.10
[download]

They are in "reverse" order and I'd like to find a Perl one-liner to put them right. I've already solved my problem with a script:

use strict;
use warnings;

open my $fh, "<", "zones.txt";
my @lines = <$fh>;
close $fh;

for (@lines) {
    chomp $_;
    my @F = split /\./, $_;
    print join ('.', reverse @F) . "\n"
}
[download]

Output would be like:

10.100.1
10.100.2
10.100.3
[download]

I'm sure there must be a one-liner with something like "perl -ape -F/./ "stuff here" zone.txt" ... but I just can't get it work. Of course I'm on Windows, so that makes the whole single quote / double quote thing a bit tricky too.

Comment on One liner help Select or Download Code

Replies are listed 'Best First'.
Re: One liner help by toolic (Bishop) on Oct 08, 2014 at 18:39 UTC
Probably not short enough to be worth it, but this works for me on unix (perl v5.12.2), and I think it has a chance to work on windows, too: `perl -anF"/\./" -E "chomp@F;say join q{.},reverse@F" zones.txt 10.100.1 10.100.2 10.100.3` [download]	[reply] [d/l]
Re^2: One liner help by VinsWorldcom (Prior) on Oct 08, 2014 at 19:55 UTC
Thanks. I did it slightly modified borrowing the -l from kennethk above: (Windows 7 x64 / Strawberry Perl v5.18.1 MSWin32-x64-multi-thread) `VinsWorldcomC:\Users\VinsWorldcom\tmp> perl -alnF"/\./" -e "print join + q{.}, reverse @F" zones.txt 10.100.1 10.100.2 10.100.3` [download]	[reply] [d/l]
Re^3: One liner help by toolic (Bishop) on Oct 08, 2014 at 20:03 UTC
Nice. And golf it down with -E/say: `perl -anlF"/\./" -E"say join q{.},reverse@F" zones.txt` [download]	[reply] [d/l]
Re^4: One liner help by kennethk (Abbot) on Oct 09, 2014 at 15:52 UTC
Re: One liner help by kennethk (Abbot) on Oct 08, 2014 at 18:16 UTC
What happens with `perl -lpe "join q{.}, reverse split /\./" zones.txt` [download] You could also `perl -F. -lpe "join q{.}, reverse @F" zones.txt` [download] but I was never a fan of -a. #11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.	[reply] [d/l] [select]
Re^2: One liner help by VinsWorldcom (Prior) on Oct 08, 2014 at 19:53 UTC
Thanks, but neither of these work for me (Windows 7 x64 / Strawberry Perl v5.18.1 MSWin32-x64-multi-thread): `VinsWorldcom@C:\Users\VinsWorldcom\tmp> perl -lpe "join q{.}, reverse +split /\./" zones.txt 1.100.10 2.100.10 3.100.10` [download] They both just seem to print the file as-is.	[reply] [d/l]
Re^3: One liner help by kennethk (Abbot) on Oct 08, 2014 at 23:26 UTC
Stupid mistake; sorry: `perl -lpe "$_=join q{.}, reverse split /\./" zones.txt` [download] #11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.	[reply] [d/l]
Re^4: One liner help by VinsWorldcom (Prior) on Oct 09, 2014 at 00:44 UTC