One embodiment of the present invention sets forth a technique for emitting coherent output from multiple threads for the printf( ) function. Additionally, parallel (not divergent) execution of the threads for the printf( ) function is maintained when possible to improve run-time performance. Processing of the printf( ) function is separated into two tasks, gathering of the per thread data and formatting the gathered data according to the formatting codes for display. The threads emit a coherent stream of contiguous segments, where each segment includes the format string for the printf( ) function and the gathered data for a thread. The coherent stream is written by the threads and read by a display processor. The display processor executes a single thread to format the gathered data according to the format string for display.