QNX Developer Support
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delay()
Suspends a calling thread for a given length of time
Synopsis:
#include <unistd.h> unsigned int delay( unsigned int duration );
Arguments:
- duration
- The number of milliseconds for which to suspend the calling thread from execution.
Library:
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
Description:
The delay() function suspends the calling thread for duration milliseconds.
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The suspension time may be greater than the requested amount, due to the scheduling of other, higher-priority threads by the system. |
Returns:
0 for success, or the number of unslept milliseconds if interrupted by a signal.
Errors:
If an error occurs, errno is set to:
- EAGAIN
- No timer resources were available to satisfy the request.
Examples:
#include <unistd.h>
#include <stdlib.h>
void play_sound( void )
{
...
}
void stop_sound( void )
{
...
}
int main( void )
{
play_sound();
delay( 500 ); /* delay for 1/2 second */
stop_sound();
return EXIT_SUCCESS;
}
Classification:
| Safety: | |
|---|---|
| Cancellation point | Yes |
| Interrupt handler | No |
| Signal handler | Yes |
| Thread | Yes |
See also:
alarm(), errno, nanosleep(), nap(), napms(), sleep()
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