test_write.c

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>

char buf[4096];
int main() {
  int fd;
  fd = open("/dev/null", O_WRONLY);
  for (int i = 0; i < (1 << 25); i++) {
    write(fd, buf, 4096);
  }
  close(fd);
  return 0;
}