Close diary file on Error

Hi, I am using the diary function to log my application output. Something like

diary(path_to_logfile)
  % all my code with output to the console, matrices written to desk, etc
diary off

When the code fails, the diary is not closed. One option would be to wrap all the code on a try-catch statement and close it on the catch.

Is there another way to avoid the diary being "open" when the app fails?

Answer 1

[Jan]

TRY-CATCH is really the best solution:

diary(path_to_logfile)
try
  % all my code with output to the console, matrices written to desk, etc
catch ME
  fprintf(1, 'ERROR:\n%s\n', ME.message);
end
diary off

This is clean an efficient, and you could insert other code for cleanup also, e.g. fclose('all').

[gire]

I was hoping for another option because I do not like having all my code wrapped by try-catch. After some research and your answer I think this is the only option. Thanks :)

Answer 2

[Walter Roberson]

onCleanup() might be appropriate for you.

Answer 3

[Andrew Janke]

The onCleanup function is what you want in modern Matlab. No try/catch to ugly up your code, and it's robust even against a dbquit.

function my_function
diary(path_to_logfile)
RAII.diary = onCleanup(@() diary('off'))
% ... now do whatever, and don't worry about closing the diary; it'll 
% be automatically closed whenever this function returns for any reason...
end

[Florian Rössing]

Super usefull, thank you

[Tria Technologies]

Upvoting the use of onCleanup I recently discovered this and it has added better predictability to functions. Of course, classes have built in delete() methods for doing the same.