2009-08-07 10:52:40     delay function in user space

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2009-08-07 10:52:40     delay function in user space

Harbhajan Singh (INDIA)

Message: 78516   

 

Hi,

 

Is there any delay function available in user space like udelay and mdelay.

 

there are usleep and msleep functions, but i need to put only the delay in user space.

 

Thank you.

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2009-08-07 11:02:45     Re: delay function in user space

Robin Getz (UNITED STATES)

Message: 78517   

 

Harbhajan:

 

What are you trying to do? You may be able to use nanosleep() - but - that will yeild to the kernel, and other processes will be scheduled in. - it is a min delay - not an actual delay.

 

-Robin

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2009-08-07 11:06:17     delay function in user space

Michael Hennerich (GERMANY)

Message: 78519   

 

I've used something like this before ....

 

void mydelay(unsigned int delay)

{

clock_t goal = delay * CLOCKS_PER_SEC / 1000 + clock();

while (goal > clock()) ;

}

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2009-08-07 11:08:25     Re: delay function in user space

Harbhajan Singh (INDIA)

Message: 78520   

 

Dear Robin,

 

I am using the i2c driver calls from the user space. for some register setting i need to poll the bit of register whether it is set properly or not. so instead of polling i can put some delay instead of doing the kernel activity (i2c read and poll)

 

Is there any way?

 

Thank you.

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2009-08-07 11:17:42     Re: delay function in user space

Robin Getz (UNITED STATES)

Message: 78521   

 

Harbhajan:

 

use nanosleep.

 

-Robin

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2009-08-07 12:00:19     Re: delay function in user space

Harbhajan Singh (INDIA)

Message: 78522   

 

Hi Robin and Micheal,

 

Thank you.

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