IRC /TOPIC command trimming issue in iOS

Question

I am using Cocoa async socket library in my iOS application to make connection with an IRC server via Tcp sockets. All the IRC commands are working perfectly except /TOPIC command. When I send a topic command it always trim the first two characters in the response. Please check the example wireshark report below.

It works on other IRC clients (mIRC). How can I identify the root cause of the issue?

Answer 1

If you send your own IRC commands (most IRC clients let you easily inject arbitrary commands with /command here), you have to format it correctly, with a : before the final parameter if it contains spaces:

TOPIC #abcdereh :My name is Clement

Most IRC clients have an alias for /TOPIC that does that stuff for you.
If you are writing your own client, make sure that you handle the following cases:

• /TOPIC: send TOPIC #currentchannel
• /TOPIC #somechannel send TOPIC #somechannel
• /TOPIC Not a channel send TOPIC #currentchannel :Not a channel
• /TOPIC #somechannel New Topic send TOPIC #somechannel :New Topic