pthread_at...schedparam(3) Library Functions Manual pthread_at...schedparam(3)
NAME
pthread_attr_setschedparam, pthread_attr_getschedparam - set/get sched-
uling parameter attributes in thread attributes object
LIBRARY
POSIX threads library (libpthread, -lpthread)
SYNOPSIS
#include <pthread.h>
int pthread_attr_setschedparam(pthread_attr_t *restrict attr,
const struct sched_param *restrict param);
int pthread_attr_getschedparam(const pthread_attr_t *restrict attr,
struct sched_param *restrict param);
DESCRIPTION
The pthread_attr_setschedparam() function sets the scheduling parameter
attributes of the thread attributes object referred to by attr to the
values specified in the buffer pointed to by param. These attributes
determine the scheduling parameters of a thread created using the thread
attributes object attr.
The pthread_attr_getschedparam() returns the scheduling parameter at-
tributes of the thread attributes object attr in the buffer pointed to
by param.
Scheduling parameters are maintained in the following structure:
struct sched_param {
int sched_priority; /* Scheduling priority */
};
As can be seen, only one scheduling parameter is supported. For details
of the permitted ranges for scheduling priorities in each scheduling
policy, see sched(7).
In order for the parameter setting made by pthread_attr_setschedparam()
to have effect when calling pthread_create(3), the caller must use
pthread_attr_setinheritsched(3) to set the inherit-scheduler attribute
of the attributes object attr to PTHREAD_EXPLICIT_SCHED.
RETURN VALUE
On success, these functions return 0; on error, they return a nonzero
error number.
ERRORS
pthread_attr_setschedparam() can fail with the following error:
EINVAL The priority specified in param does not make sense for the cur-
rent scheduling policy of attr.
POSIX.1 also documents an ENOTSUP error for pthread_attr_setsched-
param(). This value is never returned on Linux (but portable and fu-
ture-proof applications should nevertheless handle this error return
value).
ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).
┌────────────────────────────────────────────┬───────────────┬─────────┐
│ Interface │ Attribute │ Value │
├────────────────────────────────────────────┼───────────────┼─────────┤
│ pthread_attr_setschedparam(), │ Thread safety │ MT-Safe │
│ pthread_attr_getschedparam() │ │ │
└────────────────────────────────────────────┴───────────────┴─────────┘
STANDARDS
POSIX.1-2008.
HISTORY
POSIX.1-2001. glibc 2.0.
NOTES
See pthread_attr_setschedpolicy(3) for a list of the thread scheduling
policies supported on Linux.
EXAMPLES
See pthread_setschedparam(3).
SEE ALSO
sched_get_priority_min(2), pthread_attr_init(3),
pthread_attr_setinheritsched(3), pthread_attr_setschedpolicy(3),
pthread_create(3), pthread_setschedparam(3), pthread_setschedprio(3),
pthreads(7), sched(7)
Linux man-pages 6.9.1 2024-05-02 pthread_at...schedparam(3)
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