I am following Microsoft Orleans Tutotials to do the 'Hello World' and I was able to get everything compiled but when I run I get
System.Threading.Tasks.Task`1[System.String]
instead of showing 'Hello World!'. I put a break point in the return statement from the Grain and it is called after the print actually happened. It seems the execution happens even before the real grain is called. I thought the call return is a promise and should execute like closure. Am I missing something?
You need to get the result of the task.
Related
I have encountered an issue recently while processing a CICS transaction. My CICS transaction is calling a chain of dynamically linked COBOL modules. The transaction runs fine for the first time after the PGM-A load is new copied into the region. When I try to process the transaction for the second time, I keep getting CEE3DD abend saying the module not found for PGM-B which is being called from PGM-A. IF I do a new copy for PGM-A in CICS, the transaction again runs fine.
Something is wrong with the CICS setup or memory but I am not able to figure it out. PGM-A is working fine in batch processing. PGM-B has no issues when it is called from any other PGMs except PGM-A.
Can someone share some thoughts on what may be wrong with this?
To invoke your program via CICS, it must be compiled with the NODYNAM option.
It admittedly seems counter-intuitive, but using the DYNAM option will cause CICS stubs to be loaded, instead of your intended programs, and result in the CEE3501S condition.
So, compile your programs with the NODYNAM option to avoid this error condition.
See the following links for additional info:
https://www.ibm.com/support/knowledgecenter/en/SSGMCP_5.3.0/com.ibm.cics.ts.applicationprogramming.doc/topics/dfhp3_cobol_subprog_rules.html
http://www-01.ibm.com/support/docview.wss?uid=swg21054079
Does PGM-A use "CALL VARIABLE" to invoke PGM-B? If so check the contents of VARIABLE on the second run (the contents of that variable will probably be reported in the error message. The contents of the variable may be overwritten by a bug in PGM-A. That might explain why the program always fails after the (seemingly) succesful run and after a newcopy.
Converting this from dynamic to static worked. But the question remains why it was not working with dynamic linking.
If luaL_load function fails, then, according to the documentation (Lua5.1), the error message is pushed on the stack and can be retrieved with lua_tostring(L, -1), but if I want to print a customized error message, I don't think I can use lua_Debug (because that is for active function). Is there any other way (other than parsing the string) to get the file, line number and what error occured ?
--
Thanks.
The error code returned by luaL_loadfile tells you what kind of error happened. You're mostly likely only interested in LUA_ERRSYNTAX, in which case there is a detailed error message left on the stack. This is the only record of the error. If you need to reformat it, you need to parse it.
During a luaL_load(), there is nothing techinally on the stack that is relavant to the loading of the script. No functions are performed or executed in the script. Its just a compilation step, returning a function that encapsulates the whole file or the error found during compilation.
If you get a function back, you execute this to actually run the script, which sounds like what you are really interested in. In which case you can use a lua_pcall() and provide an error handler. In your handler you would then have your expected stack trace available via lua_Debug.
I was playing with the process dictionary inside a gen_server module, i called get() function and i get something like this.
{'$ancestors',[main_server,<0.30.0>]},
{'$initial_call',{child_server,init,1}}]
what happen if i erased the process dictionary, what would go wrong ?
i erased it and every thing worked fine, even
calling a function that generates an exception in the child_server the main_server still can get the exit signal.
$ancestors is used only in the initialization stage, to get the parent's PID, which is used to catch the EXIT message coming from the parent, so that the terminate stuff can get executed. Erasing this key when the server is up and running makes no difference.
$initial_call, on the other hand, is used in the crash report by proc_lib to dump the MFA info.
A quick grep in the OTP source tree can certainly help.
I think some debug functions may use process dictionary, for example erlang:process_info/2
Is there a way to define a task in Ant that always gets executed at the end of every run? This SO question provides a way to do so, at the start of every run, before any other targets have been executed but I am looking at the opposite case.
My use case is to echo a message warning the user if a certain condition was discovered during the run but I want to make sure it's echoed at the very end so it gets noticed.
use a buildlistener, f.e. the exec-listener which provides a taskcontainer for each build result
( BUILD SUCCESSFUL | BUILD FAILED ) where you can put all your needed tasks in, see :
https://stackoverflow.com/a/6391165/130683
for details.
It's an interesting situation. Normally, I would say you can't do this in an automated way. You could wrap Ant in some shell script to do this, but Ant itself really isn't a full fledge programming language.
The only thing I can think of is to add an <ant> call at the end of each task to echo out what you want. You could set it up, that if a variable isn't present, the echo won't happen. Of course, this means calling the same target a dozen or so times just to get that final <echo>.
I checked through AntXtras and Ant-Contrib for possible methods, but couldn't find any.
Sorry.
Wrap your calls in the sequential container.
http://ant.apache.org/manual/Tasks/sequential.html
I'm writing a GUI that's meant to be easily customizable by the end-users. The functions are in C++ and are called from Lua. I'm trying to make a Sleep() type function that will pause the script but not the program itself.
I was able to get it working by using threads and making one for each function. However, I want it to be an individual function. As in, instead of having it part of the CreateButton function and every other function, simply having a Delay or Sleep function that only halts the script, not the entire program.
Me being a novice at Lua, I really don't know how to go about this. Any help is appreciated.
I'd look into making a state machine using coroutines and message passing. Treat each button push like a c++ string that gets passed into coroutine resume. You can then build a little state machine that switches on the message. You can then do some UI work and then put the coroutine back to sleep till something sends it another message.
This is pretty handy if you have a state machine that does UI.
pseudo code:
c_obj:wait_for_message("mouse_down");
local message = coroutine.yield();
if(message == "mouse_down") then
update draw function.
end
c_obj:wait_for_message("mouse_up");
local message = coroutine.yield();
if(message == "mouse_up") then
Update UI..
update draw function.
end
etc...
To make your busy-waiting solution more efficient, how about using select() or similar to wait for some GUI events to process, rather than spinning? It seems like something you would need to do in the GUI regardless of the scripting side of things.