Determine Path of Mex S function from the C/C++ mex code

I have a C++ level 2 S function that I am compiling with mex. This s function loads data from external files that are located relative to the s function file itself. Say, the data is located at "..\data" relative to the s function file itself (say it is myFunction.mexw32). Is is it possible from my C++ code to determine the path the S function so that I can then determine the location of my data files? I know this is possible in a script using the mfilename('fullpath') method, but I can't find how to do it in an S function.

I really really don't want to hard code the path to the data as that will cause other issues. If I leave it relative it looks it up relative to MATLAB's current directory, not the directory of the S function (which is located elsewhere on MATLAB's path).

Thanks for any help!

Answer 1

[Kaustubha Govind]

In MATLAB, you can look up the full path to any given file using the MATLAB function which. You can call this from your S-function using mexCallMATLAB, with the S-function name passed in as the input argument. Note that the S-function name is stored in the macro S_FUNCTION_NAME which is defined at the top of every S-function.

Answer 2

[Graham Fletcher]

I realise this is quite old, but this can be achieved without needing to call back into Matlab. On Windows, I use

GetModuleHandleEx

and

GetModuleFileName

in conjunction to get the path to the mexw64.See this StackOverflow post for a fuller description.

https://stackoverflow.com/questions/6924195/get-dll-path-at-runtime

Answer 3

[Ben]

A little bit roundabout, but it works great. Thanks!