Can't compile MEX-files under OS X Lion... even with patch!

Hello!

Trying to compile the MEX example as shown here:

http://www.mathworks.co.uk/support/tech-notes/1600/1605.html#testing

Installed the patch as shown here:

http://www.mathworks.co.uk/support/solutions/en/data/1-FR6LXJ/index.html

But I get this error:

>> mex yprime.c
/var/folders/ks/xd_bvtl16fx5m10g8w6t1f9h0000gp/T//cc5jjKJx.s:unknown:FATAL:can't create output file: yprime.o

      mex: compile of ' "yprime.c"' failed.

I can't find any support anywhere in the docs. Can anyone help?

Thanks!

Louise :)

Answer 1

[louise]

SOLVED.

You need to run Matlab as root.

This is done in OS X by cd'ing to the bin directory inside the Matlab app and running the matlab executable in there with sudo.

You can write your own script to automate this.

Answer 2

[Kaustubha Govind]

Try running:

   mex -v yprime.c

This should give you a verbose output of the "mex" command that should give you a better idea of the issue.

Also, make sure that you have write permissions in your drive (on Windows 7, for example, MATLAB needs to be "run as administrator" to be able to write to disk).

[louise]

Thanks! Tried that and same output though.

[louise]

Your hint about running as admin really helped :)

Answer 3

[Ken Atwell]

Rather than run MATLAB as root, I would encourage you first copy any MEX example file that ships with MATLAB to a folder that you can write to without being root. For example:

 cd ~/Documents/MATLAB
 copyfile([matlabroot '/extern/examples/refbook/timestwo.c'])
 mex timestwo.c
 timestwo(512)

This is probably only at issue with the examples that ship with MATLAB; presumably you keep your own source code in user-writeable folders.

You also have the option of using MEX's -o switch to control where MEX writes files.

[louise]

Even better, good work Ken