sched_get_priority_min()
QNX SDP8.0C Library ReferenceAPIDeveloper
Get the minimum priority for the scheduling policy
Synopsis:
#include <sched.h>
int sched_get_priority_min( int policy );
Arguments:
- policy
 - The scheduling policy, which must be one of:
  
- SCHED_FIFO — a fixed-priority scheduler in which the highest priority ready thread runs until it blocks or is preempted by a higher priority thread.
 - SCHED_RR — similar to SCHED_FIFO, except that threads at the same priority level timeslice (round robin) every 4 × the clock period (see ClockPeriod()).
 - SCHED_OTHER — currently the same as SCHED_RR.
 - SCHED_SPORADIC — sporadic scheduling.
    For more information, see
    pthread_attr_setschedpolicy(),
    and
    
Scheduling policies
in the chapter on the microkernel in the System Architecture guide. - SCHED_HIGH_PRIORITY_IST — a FIFO scheduling policy that allows a thread to go at or above the clock IST, but below 255.Note:The SCHED_HIGH_PRIORITY_IST policy is intended only for ISTs. For more information, see
Interrupt Service Thread (IST)
in the Programmer's Guide. - SCHED_OFFLINING — a FIFO scheduling policy intended for CPU
      offlining that allows a thread to be of higher priority than the clock IST. 
      Note:
- To set the SCHED_OFFLINING policy, the process must have the
                        runstate ability enabled. For more information, go to 
Abilities
in the QNX OS System Security Guide. - The offlining and onlining scheduling feature is experimental.
 
 - To set the SCHED_OFFLINING policy, the process must have the
                        runstate ability enabled. For more information, go to 
 
 
Library:
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
Description:
The sched_get_priority_min() function returns the minimum value for the scheduling policy specified by policy.
Returns:
The appropriate minimum for success, or -1 (errno is set).
Errors:
- EINVAL
 - The value of the policy parameter doesn't represent a defined scheduling policy.
 - ENOSYS
 - The sched_get_priority_min() function isn't currently supported.
 
Classification:
| Safety: | |
|---|---|
| Cancellation point | No | 
| Signal handler | Yes | 
| Thread | Yes | 
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