I was coding in GoLang, just working on personal interests, and one of my common practices is to package any commands necessary to running a program into a "runner.bat" file. This, of course, speeds up my workflow by not forcing me to type the same command(s) a thousand times. However, I noticed that when I ran my go program (a fairly simple Naive-Bayes algorithm for data processing), it would stall out. I hit ctrl + c and it threw "exit status 2". Based purely on experimentation, I discovered that if the directory had a file called "runner.bat" the go program would stall out, with no regards towards the contents of that file. If I removed my file or renamed it, everything runs just fine. My question being, why does this happen?
Lets say I've made a pascal program. Let's say that I haven't saved the program and I mistakenly created a loop. I ran the program and I'm stuck in a loop in the DOS run screen. How do I get out without Alt+F4? The program I am using is Turbo Pascal.
If its stuck in a tight loop, you can't. But if it is writing to the screen or checking the keyboard then CTRL+C will do the trick.
Ctrl+C should do the trick, sometimes Ctrl+Break
This question already has an answer here:
How to abort a running program in MATLAB?
(1 answer)
Closed 7 years ago.
I write a long running script in Matlab, e.g.
tic;
d = rand(5000);
[a,b,c] = svd(d);
toc;
It seems running forever. Becasue I press F5 in the editor window. So I cannot press C-Break to stop in the Matlab console.
I just want to know how to stop the script. I am current use Task Manager to kill Matlab, which is really silly.
Thanks.
Matlab help says this-
For M-files that run a long time, or that call built-ins or MEX-files that run a long time, Ctrl+C does not always effectively stop execution. Typically, this happens on Microsoft Windows platforms rather than UNIX[1] platforms. If you experience this problem, you can help MATLAB break execution by including a drawnow, pause, or getframe function in your M-file, for example, within a large loop. Note that Ctrl+C might be less responsive if you started MATLAB with the -nodesktop option.
So I don't think any option exist. This happens with many matlab functions that are complex. Either we have to wait or don't use them!.
If ctrl+c doesn't respond right away because your script is too long/complex, hold it.
The break command doesn't run when matlab is executing some of its deeper scripts, and either it won't log a ctrl sequence in the buffer, or it clears the buffer just before or just after it completes those pieces of code. In either case, when matlab returns to execute more of your script, it will recognize that you are holding ctrl+c and terminate.
For longer running programs, I usually try to find a good place to provide a status update and I always accompany that with some measure of time using tic and toc. Depending on what I am doing, I might use run time, segment time, some kind of average, etc...
For really long running programs, I found this to be exceptionally useful
http://www.mathworks.com/matlabcentral/fileexchange/16649-send-text-message-to-cell-phone/content/send_text_message.m
but it looks like they have some newer functions for this too.
MATLAB doesn't respond to Ctrl-C while executing a mex implemented function such as svd. Also when MATLAB is allocating big chunk of memory it doesn't respond. A good practice is to always run your functions for small amount of data, and when all test passes run it for actual scale. When time is an issue, you would want to analyze how much time each segment of code runs as well as their rough time complexity.
Consider having multiple matlab sessions. Keep the main session window (the pretty one with all the colours, file manager, command history, workspace, editor etc.) for running stuff that you know will terminate.
Stuff that you are experimenting with, say you are messing with ode suite and you get lots of warnings: matrix singular, because you altered some parameter and didn't predict what would happen, run in a separate session:
dos('matlab -automation -r &')
You can kill that without having to restart the whole of Matlab.
One solution I adopted--for use with java code, but the concept is the same with mexFunctions, just messier--is to return a FutureValue and then loop while FutureValue.finished() or whatever returns true. The actual code executes in another thread/process. Wrapping a try,catch around that and a FutureValue.cancel() in the catch block works for me.
In the case of mex functions, you will need to return somesort of pointer (as an int) that points to a struct/object that has all the data you need (native thread handler, bool for complete etc). In the case of a built in mexFunction, your mexFunction will most likely need to call that mexFunction in the separate thread. Mex functions are just DLLs/shared objects after all.
PseudoCode
FV = mexLongProcessInAnotherThread();
try
while ~mexIsDone(FV);
java.lang.Thread.sleep(100); %pause has a memory leak
drawnow; %allow stdout/err from mex to display in command window
end
catch
mexCancel(FV);
end
Since you mentioned Task Manager, I'll guess you're using Windows. Assuming you're running your script within the editor, if you aren't opposed to quitting the editor at the same time as quitting the running program, the keyboard shortcut to end a process is:
Alt + F4
(By which I mean press the 'Alt' and 'F4' keys on your keyboard simultaneously.)
Alternatively, as mentioned in other answers,
Ctrl + C
should also work, but will not quit the editor.
if you are running your matlab on linux, you can terminate the matlab by command in linux consule.
first you should find the PID number of matlab by this code:
top
then you can use this code to kill matlab:
kill
example:
kill 58056
To add on:
you can insert a time check within a loop with intensive or possible deadlock, ie.
:
section_toc_conditionalBreakOff;
:
where within this section
if (toc > timeRequiredToBreakOff) % time conditional break off
return;
% other options may be:
% 1. display intermediate values with pause;
% 2. exit; % in some cases, extreme : kill/ quit matlab
end
I'm playing around with making a simple terminal-based game with Ruby, and I'm currently trying to come up with a way of reading input from the terminal.
So far I've been using gets, but I'd like to have the game react instantly without requiring a newline (so you don't need to press a key, THEN enter).
I've figured out I need to put the terminal in non-canonical mode, and I'm assuming I can do that by calling $stdin.ioctl. The problem is, I'm not sure what arguments or flags I should be passing to this, and the documentation and searches just lead to information about the underlying C function.
Can anyone tell me what I should be calling $stdin.ioctl with? I'm using Terminal.app/tcsh on OSX Leopard.
Edit: This is what I ended up using, thanks to MarkusQ:
%x{stty -icanon -echo}
key = STDIN.read(1)
Your problem is outside of ruby.
Easiest answer: wrap your IO in %x{stty -raw echo} and %x{stty -raw echo} to change the mode with stty.
You'll probably want to do and ensure an exit handler to make certain the mode is set back when you exit.
-- MarkusQ
I was debugging a crash in my HID driver code on the Mac and found that the crash happened in the CFRunLoop. In the driver code I open the USB handles for the devices which match the VID and the PID which match my HID device and then set up an Interrupt call back for it using setInterruptReportHandlerCallback function and then add it to the CFRunLoop using CFRunLoopAddSource call. In my call to the close handles I freed them up using CFRunLoopRemoveSource and then a CFRelease on the CFRunLoopSourceRef .
The problem occurs when I try to Open the handles wait for a while( 5ms) and then close the handles in a loop.
When I searched for the problem I came across a link where they had a similar problem to mine http://lists.apple.com/archives/usb/.../msg00099.html where they had used CFRunLoopSourceInvalidate call instead of teh Remove Source call. When I changed it to Invalidate source in my close handles call, it fixed my crash. I wanted to know what is the difference between the crash and why this call fixed my crash?
Thanks
jbsp72
First, let me thank you. I type CFRunLoopRemoveSource in google, find your message which is exactly the problem I was trying to solve, and your solution by calling CFRunLoopSourceInvalidate instead also solves my problem.
Now, the difference between CFRunLoopRemoveSource an CFRunLoopSourceInvalidate is:
CFRunLoopRemoveSource removes the
source from the specific run loop you
specify.
CFRunLoopSourceInvalidate renders the
source invalid, and will remove it
from all the run loops where was
added.
Now, the crash, which I suspect is the same as the one I got, is that the run loop the source was added to has disappeared, and trying to remove the source from it results in a crash. Actually, an infinite loop in __spin_lock in my case.
Now, how can a run loop disappear? Run loops are tied to threads. You create a new thread, you have a new run loop, automatically. If a thread ends, the run loop disappears with it. The thread I attached the run loop to has exited, and subsequently removing the source from the run loop results in the crash.
The reason why invalidating the run loop solves the problem is because it removes the source from all the run loops it was added to, ignoring run loops that now do not exist anymore.