Proposed C API function: lua_getmainthread

[Matt Campbell <mattc@...>]

Hello:

I think it would be useful to have a C API function called 
lua_getmainthread which returns the lua_State of the given state's main 
thread.  I can think of two uses for this function.  It allows C code to 
determine whether two lua_State pointers belong to the same global 
state.  More importantly, C code which needs to receive a lua_State from 
Lua and store it long-term for use by callbacks can use this function to 
make sure it has a lua_State that isn't about to go away.  Without this 
measure, C functions called from a short-lived coroutine get a lua_State 
pointer that will soon become invalid.

This lua_getmainthread function would be very easy to implement; it only 
needs to return the mainthread member of the state structure.  I'll 
probably go ahead and implement it in my copy of Lua (5.1 final).  I'm 
posting this suggestion because I figure it would be generally useful.  
Any thoughts?

--
Matt Campbell
Lead Programmer
Serotek Corporation
www.freedombox.info
"The Accessibility Anywhere People"