Re: perl head and tail command ?

Rob Dixon wrote:
Richard Lee wrote:
I would imagine linux's head command can be replaced w/ chop
I asked this because I have a filehandle which was,

open $source, '/tmp/server.txt' ( and no doing head -1 /tmp/server.txt is not an option since I need to go through some other stuff
before i need to issue below command )

and I wanted to do

my $top = `head -1 $source`
my $bottom = `tail -1 $source`

but I realized I cannot do $source in back tick.

so I imagine i can do

my $top = chop $source;

But what about the $bottom one?

The chop() function simply removes the last character from a string and returns it. Since $source isn't a string you would get an error. Your best bet is likely to be the Tie::File module. For instance

use strict;
use warnings;

use Tie::File;

tie my @file, 'Tie::File', '/tmp/server.txt' or die $!;

my ($top, $bottom) = @file[0, -1];

HTH,

Rob


when you are doing it to filehandle vs array, which consumes more memory?

my source file is about 100,000 lines...

open my $source, 'tmp/server.txt' or die !$;

VS
tie my @file, 'Tie::File', '/tmp/server.txt' or die $!;


.

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