Scotmonk:
If the file is small enough that it fits comfortably in memory, you could just read the whole thing and then reverse it, like this:
# foo.pl - print a file in reverse
use strict;
use warnings;
my $FName = shift // die "Expected a filename!";
open my $FH, '<', $FName or die "Can't open $FName: $!\n";
# Read all the lines
my @lines = <$FH>;
# Reverse the order
@lines = reverse @lines;
for my $line (@lines) {
print $line;
}
When I run it on itself, I get:
$ perl foo.pl foo.pl
}
print $line;
for my $line (@lines) {
@lines = reverse @lines;
# Reverse the order
my @lines = <$FH>;
# Read all the lines
open my $FH, '<', $FName or die "Can't open $FName: $!\n";
my $FName = shift // die "Expected a filename!";
use warnings;
use strict;
# foo.pl - print a file in reverse
Sometimes a file is too big to handle that way, though that's increasingly rare with modern computers. But if so, you could always use a program (such as tac) that will reverse the file for you, and then you can process the file in order in your code.
For one-off jobs, that's the way I'd go. But if you always need to process the files in reverse, I'd use the File::Backwards module that stevieb suggested.
...roboticus
When your only tool is a hammer, all problems look like your thumb.
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