how to schedule the compiler?

[cdrsir]

I tried the following code, which prints some message on the screen for
every minute, but this takes the whole CPU, who can tell me how to
change the code, so that it takes not so much CPU when running the
program. Thanks.


#include "stdio.h"
#include "time.h"

void main()
{
struct tm *local;
int actual_minu;
int last_minu;
time_t t;

//! initialize the actual_minu and last_minu
t = time(NULL);
local = localtime(&t);
actual_minu = local->tm_min;
last_minu = actual_minu;

while ( true )
{
t = time(NULL);
local = localtime(&t);
actual_minu = local->tm_min;
if ( actual_minu-last_minu >= 1 ) {
printf("One minute is gone!!!\n");
last_minu = actual_minu;
}
}

}

 

[mlimber]

I tried the following code, which prints some message on the screen for
every minute, but this takes the whole CPU, who can tell me how to
change the code, so that it takes not so much CPU when running the
program. Thanks.


#include "stdio.h"
#include "time.h"

void main()
{
struct tm *local;
int actual_minu;
int last_minu;
time_t t;

//! initialize the actual_minu and last_minu
t = time(NULL);
local = localtime(&t);
actual_minu = local->tm_min;
last_minu = actual_minu;

while ( true )
{
t = time(NULL);
local = localtime(&t);
actual_minu = local->tm_min;
if ( actual_minu-last_minu >= 1 ) {
printf("One minute is gone!!!\n");
last_minu = actual_minu;
}
}

}

There is no way to do this in a platform-independent fashion. Ask in a
newsgroup for your compiler or OS. See this FAQ for some possible
groups to post to:

http://www.parashift.com/c++-faq-lite/how-to-post.html#faq-5.9

Cheers! --M

 

[cdrsir]

may be you are right, but hopfully there is someone who has some ideas.

I use VC++ 6.0, Win-XP

 

[mfurnari]

Have you tried using a "Sleep" function instead of busy waiting.
Something like this:

for (int i = 0; ;i++)
{
Sleep(60000); //One minute = 1000 ms/s * 60 s/m
cout << i << " minutes have passed" << endl;
}

 

[steve.holle]

Is there a "sleep" command you could use to suspend your ap for a
specific period?

 

[cdrsir]

I think Sleep is exactly the function that I need. thanks a lot.


(e-mail address removed) 写é“：

 

[red floyd]

I tried the following code, which prints some message on the screen for
every minute, but this takes the whole CPU, who can tell me how to
change the code, so that it takes not so much CPU when running the
program. Thanks.


#include "stdio.h"
#include "time.h"

void main()
{
struct tm *local;
int actual_minu;
int last_minu;
time_t t;

//! initialize the actual_minu and last_minu
t = time(NULL);
local = localtime(&t);
actual_minu = local->tm_min;
last_minu = actual_minu;

while ( true )
{
t = time(NULL);
local = localtime(&t);
actual_minu = local->tm_min;
if ( actual_minu-last_minu >= 1 ) {
printf("One minute is gone!!!\n");
last_minu = actual_minu;
}
}

}

1. This is C code, not C++.
2. main() returns int, not void.

 

[Diego Martins]

each OS has a great variety of "sleep like" functions

with threads, this is an issue worth of investigation (and hard to make
it portable)

 

[cdrsir]

I would like to use

#ifdefine windows
call your windows related function
.....



or ifdefine linux
and call your linux related function

to handel the different system

Diego Martins 写é“：