[Swig-user] output returned twice problem

[Марк К. <soc...@gm...>]

Hello, SWIG developers and users!

I have read SWIG 2.0 and did not found answer to my question.

I have this situation:

char *nl_af2str(int, char *buf, size_t len);

'char *nl_af2str()' put data into supplied 'char * buf', and not more than 'size_t len' bytes. And also, it returns the same buffer as return value on success, or NULL on error.

So, I have in my .i file following:

%cstring_output_maxsize(char *buf, size_t len)
extern char *nl_af2str(int, char *buf, size_t len);

In that case, SWIG generate python function that returns tuple with two values - one for real value returned by my function, and second  - for the cstring_output_maxsize argument.

I want SWIG to generate function that return single value. In case when function return NULL, memory allocated for buf should be freed, and None returned. If nl_af2str returns !NULL, allocated buffer coerced to string should be returned.

Is it possible?

Maybe I should override some logic in python for generated .py file?