You may not know this (many folks don't), but no matter what the OS platform, when writing to a network socket, "\n" means <CR><LF>. ... So, yes, even on Unix, a write to network socket will be <CR><LF>, while a write to a disk file will be just <LF>.

The way you worded this actually annoyed me enough that I double-checked my knowledge on this.

serv.pl:

use warnings;
use strict;
use IO::Socket::INET;
use Devel::Peek;

my $sock = IO::Socket::INET->new(Listen => 5, LocalPort => 9000,
    LocalAddr => 'localhost',  Proto => 'tcp') or die $!;
my $cli = $sock->accept();
$cli->read(my $in, 5);
Dump($in);

[download]

cli.pl:

use warnings;
use strict;
use IO::Socket::INET;

my $sock = IO::Socket::INET->new("localhost:9000") or die $!;
print $sock "foo\n\0\0";

[download]

Output of serv.pl:

SV = PV(0x573aeb89cfe0) at 0x573aeb8e2b50
  REFCNT = 1
  FLAGS = (POK,pPOK)
  PV = 0x573aeb8ed890 "foo\n\0"\0
  CUR = 5
  LEN = 10

[download]

And, a Wireshark capture of the raw packet on the wire shows:

66:6f:6f:0a:00:00

[download]

On Linux and on Windows. You're wrong on both of those counts as well. (You can add binmode $sock, ':crlf'; to the client, and it'll be 0d0a on both platforms, as expected.)

I hope this post adds more clarity to the issue.

No, it spreads false and confusing information.

In reply to Re^7: How do I display only matches by haukex
in thread (SOLVED) How do I display only matches by tem2

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