Re: Reading the contents of a file from the bottom up

There's an API for that... File::ReadBackwards. I've never used it myself, but it appears to do what the documentation states.

Using a file called test.txt located in the same directory as the script itself which looks like this:

f
e
d
c
b
a
[download]

...and this example script:

use warnings;
use strict;

use File::ReadBackwards;

my $file = 'test.txt';

my $fh = File::ReadBackwards->new($file) 
  or die "can't read the damned '$file' file!: $!";
 
until ($fh->eof) {
    print $fh->readline;
}
[download]

...I get this output:

a
b
c
d
e
f
[download]

Comment on Re: Reading the contents of a file from the bottom up Select or Download Code

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Re^2: Reading the contents of a file from the bottom up by perlancar (Hermit) on Nov 26, 2019 at 01:05 UTC
Actually, no need for an API, sort of. There's PerlIO::reverse which lets you just add a layer when opening a file, then use your good ol' Perl API: `open my $fh, "<:reverse", "/etc/passwd"; print for <$fh>;` [download] Like File::ReadBackwards, but unlike the tac command, PerlIO::reverse only does line-by-line reversing though.	[reply] [d/l]