#include #include #include #include #define BUFFER_SIZE 1024 static char buffer[BUFFER_SIZE]; static unsigned int buffer_index = 0; static void my_putchar(const char chr) { if (buffer_index >= BUFFER_SIZE) abort(); buffer[buffer_index++] = chr; } int main() { kernaux_printf(my_putchar, "Hello, %s! Session ID: %u.", "Alex", 123); assert(strcmp(buffer, "Hello, Alex! Session ID: 123.") == 0); return 0; }