@ Original question:
If your function doesn't have formatting built into it(as seen in client_print), you can use format.
Here's an example.
Code:
new szName[32], szHostname[32], szOutput[64]
get_user_name(id, szName, 31)
get_cvar_string("hostname", szHostname, 31)
format(szOutput, 63, "Hello %s, Welcome to %s. You are player #%i.", szName, szHostname, get_user_userid(id))
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