Why can't Mex C/C++ Code With Xcode on Mac (MatlabR2015a)?

I tried to follow this example to know how to use the Legacy Code Tool :

https://www.mathworks.com/help/simulink/sfg/integrating-existing-c-functions-into-simulink-models-with-the-legacy-code-tool.html

But when I try to use the function legacy_code to create the S-function and the corresponding C MEX with this command :

% legacy_code('compile', def);

I get this error :

    % ### Start Compiling ex_sfun_doubleit
    mex('-I/Users/..../Desktop/example', '-c', '-outdir', '/private/tmp/tpaa85b6f5_b2e5_4c61_8c6e_17849ff9c5bb', '/Users/..../Desktop/example/doubleIt.c')
Building with 'Xcode with Clang'.
Error using mex
In file included from /Users/..../Desktop/example/doubleIt.c:1:
/Users/nabil/Desktop/example/doubleIt.h:1:2: error: invalid preprocessing directive
#ifndef_DOUBLEIT_H_
 ^
/Users/...../Desktop/example/doubleIt.h:2:2: error: invalid preprocessing directive
#define_DOUBLEIT_H_
 ^
/Users/...../Desktop/example/doubleIt.h:6:2: error: #endif without #if
#endif
 ^
3 errors generated.

    Error in legacycode.LCT/compile (line 352)

    Error in legacycode.LCT.legacyCodeImpl (line 84)

    Error in legacy_code (line 87)
[varargout{1:nargout}] = legacycode.LCT.legacyCodeImpl(action, varargin{1:end});

I notice Im on Mac OSX Elcapitan 10.11 and Matlab R2015a.

Thanks.

Answer 1

[James Tursa]

There are no spaces between the directive and the token. So change these lines

#ifndef_DOUBLEIT_H_
#define_DOUBLEIT_H_

to these:

#ifndef _DOUBLEIT_H_
#define _DOUBLEIT_H_