Sleeping or waiting

[Blue Ocean]

Is there any platform independent way to make a C program wait for a
certain amount of time before performing a task? I don't mean:

while(difftime( clock1, clock()) < MAGICNUMBER);

Rather, I want something that cuts down on a program's use of
processor time when it is executing, like Java's Thread.sleep(in t
milliseconds) method. Currently, whenever I write programs, they take
up 50% of my processor exactly (since I have a hyperthreading
processor, the maximum any one thread can use is fifty percent, or so
I've been lead to believe). I would like to make it so that the
program takes a step every, say, 1/60th of a second, for a physics
simulation, but I would like any spare processor time to revert to the
system idle thread.

[jacob navia]

Unix has
#include <unixstd.h>
unsigned int sleep(int seconds);

Windows has

#include <windows.h>
void Sleep(unsigned long miliseconds);

and most OSes provide the same functionality.

Look at the documentation of your system.

[jacob navia]

"jacob navia" <ja***@jacob.re mcomp.fr> a écrit dans le message de
news:cc******** **@news-reader4.wanadoo .fr...

Unix has
#include <unixstd.h>
unsigned int sleep(int seconds);

Sorry, the "seconds" argument should be unsigned int.

[Martin Ambuhl]

Blue Ocean wrote:

Is there any platform independent way to make a C program wait for a
certain amount of time before performing a task?

No. Such things are inherently OS-dependent.

[Keith Thompson]

bl*********@hot mail.com (Blue Ocean) writes:

Is there any platform independent way to make a C program wait for a
certain amount of time before performing a task? I don't mean:

while(difftime( clock1, clock()) < MAGICNUMBER);

Rather, I want something that cuts down on a program's use of
processor time when it is executing

[...]

No, there's no platform independent way of doing this. There should
be platform dependent ways of doing it on almost all platforms; for
something like this, #ifdef is your friend.

--
Keith Thompson (The_Other_Keit h) ks***@mib.org <http://www.ghoti.net/~kst>
San Diego Supercomputer Center <*> <http://users.sdsc.edu/~kst>
We must do something. This is something. Therefore, we must do this.

[Arto Huusko]

jacob navia wrote:

"jacob navia" <ja***@jacob.re mcomp.fr> a écrit dans le message de
news:cc******** **@news-reader4.wanadoo .fr...

Unix has
#include <unixstd.h>
unsigned int sleep(int seconds);

Sorry, the "seconds" argument should be unsigned int.

And the header should be #include <unistd.h>

--
Arto Huusko

[Eric Enright]

Arto Huusko wrote:

jacob navia wrote:

"jacob navia" <ja***@jacob.re mcomp.fr> a écrit dans le message de
news:cc******** **@news-reader4.wanadoo .fr...

Unix has
#include <unixstd.h>
unsigned int sleep(int seconds);

Sorry, the "seconds" argument should be unsigned int.

And the header should be #include <unistd.h>

Sorry for the OT, but since someone mentioned it..
Is "unistd" some sort of abbreviation for "unix standard" ?
I've always been curious about that header filename, and the
above seems to make sense, especially after discovering (and
subsequently reading) The Open Group's manpage for it.

If so, would anyone by chance know why the 'x' was omitted?
--
Eric Enright /"\
ericAtiptsoftDc om \ / ASCII Ribbon Campaign
X Against HTML E-Mail
Public Key: 0xBEDF636F / \

[Dan Pop]

In <sl************ *****@yamano.ti ptsoft.com> er**@tiptsoft.c om (Eric Enright) writes:

Sorry for the OT, but since someone mentioned it..
Is "unistd" some sort of abbreviation for "unix standard" ?
Sort of.
I've always been curious about that header filename, and the
above seems to make sense, especially after discovering (and
subsequently reading) The Open Group's manpage for it.

If so, would anyone by chance know why the 'x' was omitted?

Have a close look at all the C89 standard header names. The same
reason applied, apparently, in the case of <unistd.h>, too.

Dan
--
Dan Pop
DESY Zeuthen, RZ group
Email: Da*****@ifh.de

[Eric Enright]

Dan Pop wrote:

In <sl************ *****@yamano.ti ptsoft.com> er**@tiptsoft.c om (Eric Enright) writes:

Sorry for the OT, but since someone mentioned it..
Is "unistd" some sort of abbreviation for "unix standard" ?

Sort of.

I've always been curious about that header filename, and the
above seems to make sense, especially after discovering (and
subsequentl y reading) The Open Group's manpage for it.

If so, would anyone by chance know why the 'x' was omitted?

Have a close look at all the C89 standard header names. The same
reason applied, apparently, in the case of <unistd.h>, too.

Indeed, I see the similar naming convention.
Thanks for the pointer.

--
Eric Enright /"\
ericAtiptsoftDc om \ / ASCII Ribbon Campaign
X Against HTML E-Mail
Public Key: 0xBEDF636F / \

[Dan Pop]

In <sl************ *****@yamano.ti ptsoft.com> er**@tiptsoft.c om (Eric Enright) writes:

Dan Pop wrote:

In <sl************ *****@yamano.ti ptsoft.com> er**@tiptsoft.c om (Eric Enright) writes:

Sorry for the OT, but since someone mentioned it..
Is "unistd" some sort of abbreviation for "unix standard" ?

Sort of.

I've always been curious about that header filename, and the
above seems to make sense, especially after discovering (and
subsequent ly reading) The Open Group's manpage for it.

If so, would anyone by chance know why the 'x' was omitted?

Have a close look at all the C89 standard header names. The same
reason applied, apparently, in the case of <unistd.h>, too.

Indeed, I see the similar naming convention.

It's not the similar naming convention, it's the fact that no standard
header name exceeds 8 characters (the .h suffix included). unixstd.h
would take 9 characters. The care for not exceeding the 8 character limit
is obvious, as stddef.h and stdarg.h would have looked better with an s
at the end (before the suffix).

This implicit 8 character limit is gone in C99, where one can find
something as wide as inttypes.h.

Dan
--
Dan Pop
DESY Zeuthen, RZ group
Email: Da*****@ifh.de