Time ./a.out equivalent in Windows

**santosh** · Mar 16 '08, 09:55 PM

Re: Time ./a.out equivalent in Windows

Karthigan Srinivasan wrote:

Is there an equivant method of
>
'time ./a.out'
>
in Windows to measure execution time for a program?
>
Best Regards,
Karthigan.

Download the package available at the following link:

<http://unxutils.source forge.net/>

**Keith Thompson** · Mar 16 '08, 10:05 PM

Re: Time ./a.out equivalent in Windows

"Karthigan Srinivasan" <karthigan@eart hlink.netwrites :

Is there an equivant method of
>
'time ./a.out'
>
in Windows to measure execution time for a program?

We don't know. Well, some people here might happen to know, but this
isn't the place to ask, since your question really isn't about the C
programming language.

Try one of the comp.os.ms-windows.* or microsoft.* newsgroups.

--
Keith Thompson (The_Other_Keit h) <kst-u@mib.org>
Nokia
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"

**Bartc** · Mar 16 '08, 10:45 PM

Re: Time ./a.out equivalent in Windows

"Karthigan Srinivasan" <karthigan@eart hlink.netwrote in message
news:op.t74o4kv wpinhaa@karthig an-desktop...

Is there an equivant method of
>
'time ./a.out'
>
in Windows to measure execution time for a program?

I put together the C program below which vaguely works, but you might get
ideas on how to do it properly. (I've never used command parameters in C
before).

--
Bart

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

int main(int n,char **cmds)
{char cmdstring[260];
int t;
int i,m;
char **p;

if (n<=1)
{if (n==1) printf("Usage: %s filename\n",*cm ds);
return EXIT_FAILURE;
};

++cmds; /* first param of interest, should be exe name */

/* must check all params combined fit into cmdstring (you can ignore this if
not posting your code!) */
m=0;
p=cmds;
for (i=2; i<=n; ++i) m+=(strlen(*p++ )+1);
if (m>sizeof(cmdst ring)) return EXIT_FAILURE;

/* All the trouble the system went to to separate the params, now we need to
join them all together again with spaces between */
/* Hint: if you can use Winmain() instead, the params are already joined up
*/

strcpy(cmdstrin g,*cmds);
for (i=3; i<=n; ++i)
{strcat(cmdstri ng," ");
strcat(cmdstrin g,*(++cmds));
};

printf("Executi ng %s ...\n",cmdstrin g);

t=clock();

system(cmdstrin g);

t=clock()-t;

printf("Executi on time: %d msec",t);

return EXIT_SUCCESS;
}

**santosh** · Mar 16 '08, 11:05 PM

Re: Time ./a.out equivalent in Windows

Bartc wrote:

<snip>

I think you should divide the difference by CLOCKS_PER_SEC to get the
result in seconds. As such your program's result is always zero. This
is because you are strong a return value of type clock_t into an int.
Use a clock_t variable.

Also you could use malloc for concatenating the command arguments to
deal with large number of/long strings.

**santosh** · Mar 16 '08, 11:15 PM

Re: Time ./a.out equivalent in Windows

Bartc wrote:

<snip>

Since your program is paused by the operating system when the command
given to *system* is executing, both the return values from clock will
be the same, and thus the difference will always be zero.

You need to use functions beyond the C standard like POSIX *times*
function in sys/times.h to do this properly.

**Kaz Kylheku** · Mar 16 '08, 11:15 PM

Re: Time ./a.out equivalent in Windows

On Mar 16, 3:41 pm, "Bartc" <b...@freeuk.co mwrote:

t=clock();
>
system(cmdstrin g);
>
t=clock()-t;
>
printf("Executi on time: %d msec",t);

This output lies to the user if CLOCKS_PER_SEC isn't 1000.

**Bartc** · Mar 16 '08, 11:25 PM

Re: Time ./a.out equivalent in Windows

"santosh" <santosh.k83@gm ail.comwrote in message
news:frk9h0$qbu $1@registered.m otzarella.org.. .

Bartc wrote:
>
<snip>
>
Since your program is paused by the operating system when the command
given to *system* is executing, both the return values from clock will
be the same, and thus the difference will always be zero.

That's a good point. clock() should give the execution time of the program
doing the timing.

Nevertheless, it seemed to work! Or at least gave sensible results.

Maybe something to with Windows, and the OP wanted this on Windows.

--
Bart

**santosh** · Mar 17 '08, 12:15 AM

Re: Time ./a.out equivalent in Windows

santosh wrote:

<snip>

Well it is horribly broken in the sense that it will collapse all it's
arguments without preserving a space between them. A quick workaround
is to enclose all the arguments to the program inside a pair of double
quotes. Fixing it is left to the OP. :-)

**Bartc** · Mar 17 '08, 12:25 AM

Re: Time ./a.out equivalent in Windows

"santosh" <santosh.k83@gm ail.comwrote in message
news:frkcjg$6vd $1@registered.m otzarella.org.. .

Bartc wrote:
>

>>
>"santosh" <santosh.k83@gm ail.comwrote in message
>news:frk9h0$qb u$1@registered. motzarella.org. ..

>>Bartc wrote:
>>>
>><snip>
>>>
>>Since your program is paused by the operating system when the command
>>given to *system* is executing, both the return values from clock
>>will be the same, and thus the difference will always be zero.

>>
>That's a good point. clock() should give the execution time of the
>program doing the timing.
>>
>Nevertheless , it seemed to work! Or at least gave sensible results.
>>
>Maybe something to with Windows, and the OP wanted this on Windows.

>
Here is a more robust version of 'time'. Still not as good as the UNIX
version of course. This code is NOT standard C; it depends on
*gettimeofday* , which is specific to POSIX systems.
>
#include <stdio.h>

....

gettimeofday(&s tart, NULL);

....

Yes, that's pretty comprehensive, compared to my poor effort.

I see that you're measuring elapsed time, rather than execution time, which
I suppose is a good alternative (I sometimes just use my watch).

--
Bart

**santosh** · Mar 17 '08, 12:25 AM

Re: Time ./a.out equivalent in Windows

Bartc wrote:

>
"santosh" <santosh.k83@gm ail.comwrote in message
news:frk9h0$qbu $1@registered.m otzarella.org.. .

>Bartc wrote:
>>
><snip>
>>
>Since your program is paused by the operating system when the command
>given to *system* is executing, both the return values from clock
>will be the same, and thus the difference will always be zero.

>
That's a good point. clock() should give the execution time of the
program doing the timing.

It does. Trouble is, the execution of our program is suspended when the
argument to system is running. As far as clock is concerned, no time
has elapsed between the call to system and it's return.

To stick to pure standard C we will have to use the time function, whose
resolution is usually isn't sufficient for use in a "time" command.

<snip>

**Keith Thompson** · Mar 17 '08, 01:55 AM

Re: Time ./a.out equivalent in Windows

"Bartc" <bc@freeuk.comw rites:

"Karthigan Srinivasan" <karthigan@eart hlink.netwrote in message
news:op.t74o4kv wpinhaa@karthig an-desktop...

>Is there an equivant method of
>>
>'time ./a.out'
>>
>in Windows to measure execution time for a program?

>
I put together the C program below which vaguely works, but you might get
ideas on how to do it properly. (I've never used command parameters in C
before).

[snip]

The Unix/Linux "time" command cannot be implemented in purely standard
C. There are various versions of the "time" command, some of them
built into various shells. It typically reports the wall-clock time,
the user-mode CPU time, the system-mode CPU time, and the percentage
of time spent in CPU time; it may also report various I/O statistics.

--
Keith Thompson (The_Other_Keit h) <kst-u@mib.org>
Nokia
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"

**Kenny McCormack** · Mar 17 '08, 02:55 AM

Re: Time ./a.out equivalent in Windows

In article <87fxuqcdxg.fsf @kvetch.smov.or g>,
Keith Thompson <kst-u@mib.orgwrote:

>"Bartc" <bc@freeuk.comw rites:

>"Karthigan Srinivasan" <karthigan@eart hlink.netwrote in message
>news:op.t74o4k vwpinhaa@karthi gan-desktop...

>>Is there an equivant method of
>>>
>>'time ./a.out'
>>>
>>in Windows to measure execution time for a program?

>>
>I put together the C program below which vaguely works, but you might get
>ideas on how to do it properly. (I've never used command parameters in C
>before).

>[snip]
>
>The Unix/Linux "time" command cannot be implemented in purely standard C.

True, given that the C standard doesn't admit of any kind of
multi-processing, so the whole concept is moot.

You, of all people, ought to know that.

**Kenny McCormack** · Mar 17 '08, 02:55 AM

Re: Time ./a.out equivalent in Windows

In article <73068f5f-7fdd-422e-b2e5-14dec045a7fb@s8 g2000prg.google groups.com>,
Kaz Kylheku <kkylheku@gmail .comwrote:
....

>GetTickCount ...