Permission to write into text file

Hello

I got the following error below:

Permission denied : I am unable to open file mojo.txt

find the code below

function savechangeptsButtonPushed(app, event)
            writematrix(app.UITable.Data, 'mojo.txt')
        end
    end

What do I do to solve the issue

Thanks in advance

[Rik]

What is the current folder during that call? Are you sure you have write access in the first place?

[Tino]

Yes I have write access Rik and I do not know why am getting the error

[Geoff Hayes]

Tino - try creating and writing the file to a different folder (one where you have read and write permissions).

[dpb]

Use debugger and ensure you're where you think you are when the callback executes...it appears there are no returned optional diagnostic messages available from writematrix to give any additional klews like what can help from fopen and friends.

In fact, using fopen instead with the optional error return might be of interest/benefit.

[Guillaume]

Another possibility is that the file is already opened (with write access) by some other program. In any case, matlab just asks the OS to open the file for write access. It's the OS that tells matlab it's not possible. Nothing matlab can do anything about.

[dpb]

"...Nothing matlab can do anything about."

Other than trap the OS error and report it which may (or may not) be more informative to the user than just "I can't do that!" and die.

Answer 1

[Jan]

Do not use 'mojo.txt' as file name without a path. Remember, that any GUI or timer callback could call cd to change the current folder unexpectedly.

function savechangeptsButtonPushed(app, event)
folder = tempdir;  % Insert your preferred folder here
file   = fullfile(folder, 'mojo.txt');
try
  writematrix(app.UITable.Data, file);
catch ME
    error(['Cannot create file: %s', newline, '%s'], file, ME.message);
end
end

[Tino]

Hi Jan

Thanks for your response

I am not getting any error but the data is not written to the text file

How do I solve this

Thanks in advance

[Tino]

Located the files lol