It's pretty well spelled out in the pack documentation. C for unsigned char (byte), n for unsigned 16-bit short in network order, N for 32-bit long in network order, a for "arbitrary binary data".

Don't be confused by the 32-bit CCCC's, since an IP address is 4 8-bit numbers, not a 32-bit number.

In reply to Re^5: Need help with (un)pack templates by gmargo
in thread Need help with (un)pack templates by Subop

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