Timing programs in C

[hariharan_00]

Hello Friends,
I am stuck in the coding of C language. I am new to the C programming language. And I am trying to make a solar system program. I'm trying to use the functions getrusage or times, or the time command to time my programs. But I am not getting the desired results for that. I was wondering if anybody could help me with timing in C. Does anyone know how to use Timing programs in C.?? Please try to help me immediately.
Thanks in Advance.!!

[MindSpace]

Since you are new in C programming language, I think that you should know something basic about the timings that are used in the programming language. Uses of time functions include:

1. timing programs and functions.
2. telling the time.
3. setting number seeds.

Some of the basic time functions are prototypes as follows:

time_t time(time_t *tloc)
This command will return the time since 00:00:00 GMT, Jan. 1, 1970,
which is measured in seconds.

[Modifier]

You can use the different functions while including that function in #include <time.h>. The two other functions are described as follows :

• char *ctime(time_t *clock),
• char *asctime(struct tm *tm)

ctime() converts a long integer, pointed to by clock, to a 26-character string of the form produced by asctime().
asctime() converts a time value contained in a tm structure to a 26-character string of the form:
Sun Sep 16 01:03:52 1973
Also the asctime() returns a pointer to the string.

[Allan.d]

I am providing you the simple program that illustrates that calling the time function at distinct moments.

/* timer.c */
 
#include <stdio.h>
#include <sys/types.h>
#include <time.h>
 
main()
  {  int i;
				 time_t t1,t2;
 
				 (void) time(&t1);
				 for (i=1;i<=250;++i)
				   printf(``%d %d %d\n'',i, i*i, i*i*i);
				  (void) time(&t2);
				  printf(``\n Time to do 250 squares and
				 cubes= %d seconds\n'', (int) t2-t1);
		 }

[Warner]

I think that you can also use the SetTimer(); for setting the Timing programs in C. Its event driven so if you do:
SetTimer(1, 50, NULL);
By using this you can call the function OnTimer(); every 50 milliseconds. Also you have not told that exactly how your program is set. So I can't tell you how to use OnTimer(); properly. I just right click on my dlg class and select "add windows message handler" then add "WM_TIMMER" which is declared as "afx_msg void OnTimer(UINT nIDEvent);" I hope that the OnTimer(); will help you to set the Timings.

[void]

You can also try the following coding that I have made for setting the timings in C program. Here is the coding for that :

#include<stdio.h>
#include<sys/time.h>
#include<stdlib.h>
#include<sys/resource.h>
       
double getcputime();

      int main(void)
      {
      int i, n, a;
      double t;
      n = 15;
      printf("The 5-times Table\n");
      for(i=1;i<n;i++)
      {
      a = (i * 5);
      printf("%d\t%d\n", i, a);
      }
       
      printf("\n");
      t = getcputime();
      printf("The total time taken by the system is: %d (in decimal format)\n", t);
       
      return 0;
      }
 
      double getcputime(void)
      {
      double t;
      struct timeval tim;
      struct rusage ru;
      getrusage(RUSAGE_SELF, &ru);
      tim=ru.ru_stime;
      t=(double)tim.tv_sec * 1000000.0 + (double)tim.tv_usec;
      return t;
      }