rtPrintf doesn't print until destroying the context (unresolved, win7 64 and linux tested)

another problem, that i’m facing right now, is that rtPrintf doesn’t work as desired. It’s possible to reproduce with the sample1 from the optix SDK.

what i did:

rtPrintf( "Hello from index %u, %u!\n", launch_index.x, launch_index.y );

to draw_color.cu


RT_CHECK_ERROR( rtContextSetPrintEnabled(context, 1) );
RT_CHECK_ERROR( rtContextSetPrintBufferSize(context, 1000) );

to sample1.c, tested lines 105/106 (before rtContextCompile()) and 109/110 (after rtContextCompile(), but before rtContextLaunch2D()).

the problem is that it doesn’t print until either the context is destroyed or some internal buffer (which has a different size than PrintBufferSize) is filled up. I tried to use std::cout.flush() and fflush(stdout), but it didn’t help.

I have a GeForce GTX 550 Ti, AMD QuadCore, OptiX 3.5.1, CUDA 5.5 and the driver version is 335.23. operating system is win7.

I’m also putting this info here:

I managed to reproduce the problem on linux (kernel 3.11.10-7, 64bit, OpenSuse 13.1, driver 331.49, same cuda and optiX versions)