View file File name : typemaps.swg Content :/* ----------------------------------------------------------------------------- * typemaps.swg * * Tcl Pointer handling * * These mappings provide support for input/output arguments and common * uses for C/C++ pointers. * ----------------------------------------------------------------------------- */ // INPUT typemaps. // These remap a C pointer to be an "INPUT" value which is passed by value // instead of reference. /* The following methods can be applied to turn a pointer into a simple "input" value. That is, instead of passing a pointer to an object, you would use a real value instead. int *INPUT short *INPUT long *INPUT long long *INPUT unsigned int *INPUT unsigned short *INPUT unsigned long *INPUT unsigned long long *INPUT unsigned char *INPUT bool *INPUT float *INPUT double *INPUT To use these, suppose you had a C function like this : double fadd(double *a, double *b) { return *a+*b; } You could wrap it with SWIG as follows : %include <typemaps.i> double fadd(double *INPUT, double *INPUT); or you can use the %apply directive : %include <typemaps.i> %apply double *INPUT { double *a, double *b }; double fadd(double *a, double *b); */ // OUTPUT typemaps. These typemaps are used for parameters that // are output only. The output value is appended to the result as // a list element. /* The following methods can be applied to turn a pointer into an "output" value. When calling a function, no input value would be given for a parameter, but an output value would be returned. In the case of multiple output values, they are returned in the form of a Tcl tuple. int *OUTPUT short *OUTPUT long *OUTPUT long long *OUTPUT unsigned int *OUTPUT unsigned short *OUTPUT unsigned long *OUTPUT unsigned long long *OUTPUT unsigned char *OUTPUT bool *OUTPUT float *OUTPUT double *OUTPUT For example, suppose you were trying to wrap the modf() function in the C math library which splits x into integral and fractional parts (and returns the integer part in one of its parameters).K: double modf(double x, double *ip); You could wrap it with SWIG as follows : %include <typemaps.i> double modf(double x, double *OUTPUT); or you can use the %apply directive : %include <typemaps.i> %apply double *OUTPUT { double *ip }; double modf(double x, double *ip); The Tcl output of the function would be a tuple containing both output values. */ // INOUT // Mappings for an argument that is both an input and output // parameter /* The following methods can be applied to make a function parameter both an input and output value. This combines the behavior of both the "INPUT" and "OUTPUT" methods described earlier. Output values are returned in the form of a Tcl tuple. int *INOUT short *INOUT long *INOUT long long *INOUT unsigned int *INOUT unsigned short *INOUT unsigned long *INOUT unsigned long long *INOUT unsigned char *INOUT bool *INOUT float *INOUT double *INOUT For example, suppose you were trying to wrap the following function : void neg(double *x) { *x = -(*x); } You could wrap it with SWIG as follows : %include <typemaps.i> void neg(double *INOUT); or you can use the %apply directive : %include <typemaps.i> %apply double *INOUT { double *x }; void neg(double *x); Unlike C, this mapping does not directly modify the input value (since this makes no sense in Tcl). Rather, the modified input value shows up as the return value of the function. Thus, to apply this function to a Tcl variable you might do this : x = neg(x) Note : previous versions of SWIG used the symbol 'BOTH' to mark input/output arguments. This is still supported, but will be slowly phased out in future releases. */ #if defined(SWIG_INOUT_NODEF) %apply_checkctypes(%typemaps_inoutn) %apply size_t& { std::size_t& }; %apply ptrdiff_t& { std::ptrdiff_t& }; #endif