linux计算程序运行时间

 #include <stdio.h>
  #include <sys/time.h>
  #include <time.h>
 
  
  struct timeval tvpre, tvafter;
  gettimeofday(&tvpre, NULL);
  sleep(3);  //这里是linux编程,这个sleep是秒为单位的
   gettimeofday(&tvafter, NULL);
 
  ast_log(LOG_NOTICE,"prepaid_staff_log: test spend time is %d msecond.\n", (tvafter.tv_sec-tvpre.tv_sec)*1000+(tvafter.tv_usec-tvpre.tv_usec)/1000);