First, I doubt your $buffer contains a message, except by luck. But if it does, why not just do 

$buffer = "\x{12}\x{34}\x{56}" . $buffer;

[download]
or equivalent 
$buffer = (map chr, 0x12, 0x34, 0x56) . $buffer;

[download]

BTW, are messages in $buffer binary?

Assuming $buffer is being populated by sysread, $buffer is a string where each character represents a byte.

In reply to Re: How can I modify received socket messages in Perl? by ikegami
in thread How can I modify received socket messages in Perl? by bonny95

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