Re: Running the GC to clear resource holding object on failure

[Tom N Harris <telliamed@...>]

On Saturday, August 02, 2014 01:38:17 PM Marc Balmer wrote:
> The Lua script is called from C code using lua_pcall(). Now we notice a
> problem:  What if the script contains an error and p:close() is never
> called?  In this case the connection to the printer remains open until the
> GC kicks in, which can take long.  And during this time, our networked
> (ticket) printer is blocked.

You want RAII[1]. Although not baked into the language, there are a few ways 
to accomplish it with Lua. I had my own go at it[2] that works pretty well in 
5.2.

[1] http://lua-users.org/wiki/ResourceAcquisitionIsInitialization
[2] http://www.whoopdedo.org/doku/lua/index

-- 
tom <telliamed@whoopdedo.org>