/* * Test name: speed.c * * Objetive:  Test the time it takes for select to run.  *  * Description: This tests creates a number of udp connections and performs  * a select call waiting on them for reading with timeout of 0. * This is done 10,000 thousands of times and then the average time it takes * is computed * * Jose M. Gomez */#include <sys/types.h>#include <fcntl.h>#include <unistd.h>#include <sys/select.h>#include <sys/asynchio.h>#include <stdio.h>#include <stdlib.h>#include <limits.h>#include <net/netlib.h>#include <time.h>#define NUMBER 12void main(void) {	char *udp_device;	int fd[NUMBER];	fd_set fds_write;	struct timeval timeout;	time_t start_time, end_time;	int i;	FD_ZERO(&fds_write);	for (i = 0; i < NUMBER; i++) {		fd[i] = open("/dev/tty", O_RDWR);		if (fd[i] < 0) {			fprintf(stderr, "Error opening tty %d\n", i); 			exit(-1);		}		FD_SET(fd[i], &fds_write);	}		printf("Select will send 1 msg to terminal and %d to inet: \n", NUMBER);	timeout.tv_sec = 0;	timeout.tv_usec = 0;	/* get initial time */	start_time = time(NULL);	for (i = 0; i < 32000; i++) {		select(NUMBER + 4, NULL, &fds_write, NULL, &timeout); 	}	/* get final time */	end_time = time(NULL);	printf("The select call took on average: %f\n", (float)(end_time - start_time) /  32000.0);	for (i = 0; i < NUMBER; i++) {		close(fd[i]);	}}