#include "apue.h"#include <sys/times.h>static void	pr_times(clock_t, struct tms *, struct tms *);static void	do_cmd(char *);intmain(int argc, char *argv[]){	int		i;	setbuf(stdout, NULL);	for (i = 1; i < argc; i++)		do_cmd(argv[i]);	/* once for each command-line arg */	exit(0);}static voiddo_cmd(char *cmd)		/* execute and time the "cmd" */{	struct tms	tmsstart, tmsend;	clock_t		start, end;	int			status;	printf("\ncommand: %s\n", cmd);	if ((start = times(&tmsstart)) == -1)	/* starting values */		err_sys("times error");	if ((status = system(cmd)) < 0)		/* execute command */		err_sys("system() error");	if ((end = times(&tmsend)) == -1)		/* ending values */		err_sys("times error");	pr_times(end-start, &tmsstart, &tmsend);	pr_exit(status);}static voidpr_times(clock_t real, struct tms *tmsstart, struct tms *tmsend){	static long		clktck = 0;	if (clktck == 0)	/* fetch clock ticks per second first time */		if ((clktck = sysconf(_SC_CLK_TCK)) < 0)			err_sys("sysconf error");	printf("  real:  %7.2f\n", real / (double) clktck);	printf("  user:  %7.2f\n",	  (tmsend->tms_utime - tmsstart->tms_utime) / (double) clktck);	printf("  sys:   %7.2f\n",	  (tmsend->tms_stime - tmsstart->tms_stime) / (double) clktck);	printf("  child user:  %7.2f\n",	  (tmsend->tms_cutime - tmsstart->tms_cutime) / (double) clktck);	printf("  child sys:   %7.2f\n",	  (tmsend->tms_cstime - tmsstart->tms_cstime) / (double) clktck);}