A common misconception in socket programming is that \n will be \012 everywhere. In many common Internet protocols, \012 and \015 are specified, and the values of Perl's \n and \r are not reliable since they vary from system to system:

print SOCKET "Hi there, client!\015\012";  # right
print SOCKET "Hi there, client!\r\n";      # wrong
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However, using \015\012 (or \cM\cJ, or \x0D\x0A, or even v13.10) can be tedious and unsightly, as well as confusing to those maintaining the code. The Socket module supplies some Right Things for those who want them:

use Socket qw(:DEFAULT :crlf);
print SOCKET "Hi there, client!$CRLF"      # right
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When reading from a socket, remember that the default input record separator $/ is \n, which means you have to do some extra work if you're not sure what you'll be seeing across the socket. Robust socket code should recognize either \012 or \015\012 as end of line:

use Socket qw(:DEFAULT :crlf);
local ($/) = LF;     # not needed if $/ is already \012

while (<SOCKET>) {
    s/$CR?$LF/\n/;   # replace LF or CRLF with logical newline
}
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