Re: LuaTask and other thread libraries

[Daniel Quintela <dq@...>]

Daniel Quintela escribió:
> Francisco Sant'anna escribió:
> > Hello,
> >
> > When the use of threads is required, what's the best option I have?
> > I found:
> > 1 - www.cs.princeton.edu/~diego/professional/ 
> > <http://www.cs.princeton.edu/%7Ediego/professional/>*luathread*/
> > *2 - lua*51*pthread*.*lua*forge.net/ <http://forge.net/>
> > 3 - luaforge.net/projects/ <http://luaforge.net/projects/>*luatask*/
> > I chose LuaTask because of its simplicity and straightforward use.
> >
> > Also, I couldn't find an active LuaTask forum or list, sorry for 
> > posting here.
> >
> > When a thread raises an error, how am I supposed to notice it?
> > I can use task.isrunning() but where's the error message?
> > In the simple example below I can never see the message "hello error".
> >
> > -- t1.lua
> > require 'task'
> > task.create't2.lua'
> >
> > -- t2.lua
> > error'hello error'
> >
> > Thanks. 
>
> Hi Francisco,
>
> There is a forum at http://luaforge.net/forum/forum.php?forum_id=203
>
> About your example:
> 1) t1.lua (the main task) must do something after task.create() to 
> avoid terminating the whole program.
>    -- t1.lua
>    require 'task'
>    task.create't2.lua'
>    task.receive( -1 ) -- main task blocked forever
> 2) The "error" function push the error message on the stack and 
> terminates the pcall.
>    LuaTask doesn't invoke a report function (message printing) as lua 
> binary does, and you never see (or get) the message.
>    You can replace "error" by "print" in t2.lua to successfully run 
> your example.
>
> Regards,
> Daniel
Here is a simple rewrite of the example:


-- t1.lua
require 'task'
task.create( 't2.lua')
local msg, flags = task.receive( -1 )
if flags then print( msg ) end

-- t2.lua
local ok, err = pcall( function()

print( 'printing inside t2' )
error( 'hello error' )

end )
if ok then task.post( 1, '', 0 ) else task.post( 1, err or '?', -1 ) end


Regards,
Daniel