Context attached to a command?

[Andrew Cagney]

Hello,

Do any of the existing command.h functions allow you to associate some
sort of context with the command?
For instance, add_cmd() takes a function

	callback(char*arg, int from_tty);

the assumption being that the function can pick up any relevant data
from globals.  Is there an equivalent:

	calloback(void *context, char *arg, int from_tty);

where ``context'' was passed to the original add_command?  If not, I'll
add it.

	Andrew