do_who.h

linuxunix 下的c语言实现

#include <utmp.h>


void do_who(){
	struct utmp *u;
	struct timeval *val;

	while((u=getutent())){
		val = &(u->ut_tv);
		time_t *timep =(time_t*) val;

		if(u->ut_type == USER_PROCESS)
		  printf("%s  %s           %s\n", u->ut_user, u->ut_line, /*u->ut_host,*/ ctime(timep) );
		
	}

	endutent();
}