[Pharo-project] Native Boost Basics: passing char* buffer

Jan. 1, 2013

      I am trying to work with memory addresses back n forth..

Simple case of char* buffer that needs to be filled in by dll . Buffer does
not change in Pharo after the call. Am I missing something here..

The memory address that is printed out does not match what I see in Pharo /
infact the address does not change at all... for repeated call invoked from
debugger.

C Code:

DLLEXPORT int readAndWritePipe(char* outBuf )
{
          system("Echo readAndWritePipe" );
          debugPrintf ( "readAndWritePipe: %d \n" , &outBuf , 1046 );
          memcpy ( outBuf , "Testing123\0" , 11) ;
          return 0;
}

void debugPrintf ( char* logString, int intArg , char* strArg, int size )
{ // can redirect as needed to logger end point..
             FILE * logFile = fopen( "c:\\temp\\writePipes.log" , "a" );
             char* buf = (char*) calloc( sizeof(char) , size );
             sprintf( buf, logString , intArg , strArg );
             fputs(buf , logFile );
             fclose(logFile);
}

Pharo:

testPharoBuffer: buf

    <primitive: #primitiveNativeCall module: #NativeBoostPlugin error:
errorCode >
     ^ self nbCall:  #( int readAndWritePipe( String buf  ) ) module:
'TestPharo.dll'

testPharoBuffer
"self new testPharoBuffer "
    | buf addr  addr2 |
        buf := String new: 100000.
        addr := buf asNBExternalString.
        addr2 := ( NativeBoost allocate: 256 ).
        self testPharoBuffer: addr . " or use addr2, both of it does not
work"
        Transcript cr; show: buf.

[Pharo-project] Native Boost Basics: passing char* buffer

S Krish