minitrace.c

static void tracef(const char *fmt, ...)
{
	static int first = 1;
	static FILE *trace_file = NULL;
	if (first) {
		trace_file = fopen("/sys/kernel/tracing/trace_marker", "w");
		first = 0;
	}
	if (trace_file) {
		va_list args;
		va_start(args, fmt);
		vfprintf(trace_file, fmt, args);
		va_end(args);

		fprintf(trace_file, "\n");
		fflush(trace_file);
	}
}