How to implement "time" in Windows ?

[TmX]

In *nix, there the time utility for measuring the execution time of a command

I'm interested in writing my own, so here's my quick attempt :

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <time.h>

int main(int argc, char *argv[]){
	clock_t start,end;
	int x;
	char command[100];

	if (argc > 1){
		strcpy(command," ");

		for (x = 1; x < argc; x++){
			strcat(command,argv[x]);
			strcat(command," ");
		}

		start = clock();
		system(command);
		end = clock();
		printf("%f\n",(float)(end-start)/CLOCKS_PER_SEC);
	}
	return 0;

}

I don't think it perform correctly, probably due to the overhead caused by system().
How can I make it more accurate ? Maybe some Win32 API needed ?

[abachler]

GetLocalTime()

http://msdn.microsoft.com/en-us/libr...38(VS.85).aspx

[matsp]

Describe "not working properly". Yes, system will have some overhead, but that's not necessarily the only reason. If you really want to precisely measure another process, you probably will want to use CreateProcess() so that you can control the process better, and use GetProcessTimes() to get the time used by that process.

Yes, that's a whole lot more complicated, but it's more precise - unfortunately, there's no SIMPLE way to do that.

--
Mats