in reply to Split a binary file in pieces

#!/usr/bin/perl

$/ = \10_000_000;   # according to IEEE, otherwise \10_485_760

open my $in, "<", $ARGV[0] or die $!;
binmode $in;
my $n = 1;
while (<$in>) {
    open my $out, ">", "outfile_".$n++ or die $!;
    binmode $out;
    print $out $_;
}

[download]

Update: changed <> to a manually opened <$in>, because I couldn't find a sensible way to binmode ARGV...  Does anyone know how to do it?

Update-2:  use open IN => ':raw'; does seem to work for <>.  Or something ugly as 

while (<>) {
    binmode(ARGV), seek(ARGV,0,0), next if $.==1;
    ...

[download]

Replies are listed 'Best First'.
Re^2: Split a binary file in pieces
by ZJ.Mike.2009 (Scribe) on Mar 10, 2010 at 04:44 UTC
    I'm learning Perl. Thanks for the code. But how do we join the split pieces together? Thanks :)
[reply]
      Write out how you would do it in words, then translate words into code
[reply]

        You're right :) I'm thinking sometimes because the Perl community is too kind and helpful, I'm just tempted to become very very lazy :)

        Anyway I tried translating words into code and came up with the following ugly code, which seems to be working. But I know it's ugly :) 

        use strict;
use warnings;

$/ = \20_000_000; #I've just split a 20-meg file
open my $f1, "<", '1' or die $!; # piece 1 is named 1
binmode $f1;
open my $f2, "<", '2' or die $!; # piece 2 is named 2
binmode $f2;
while(my $x = <$f1>){
    while(my $y = <$f2>){
    open my $out, ">", "outfile" or die $!;
    binmode $out;
    print $out $x.$y;
    }
}

        [download]

        UPDATE: tried optimizing a few lines. It looks a little cleaner 

        use strict;
use warnings;

$/ = \20_000_000; #I've just split a 20-meg file into 2 pieces
open my $f1, "<", '1' or die $!; piece 1 is named 1
binmode $f1;
open my $f2, "<", '2' or die $!; # piece 2 is named 2
binmode $f2;
while(defined(my $x = <$f1>) && (my $y = <$f2>)){
    open my $out, ">", "outfile" or die $!;
    binmode $out;
    print $out $x.$y;
}

        [download]
[reply]
[d/l]
[select]

In Section Seekers of Perl Wisdom