PTHREAD_ATTR_GETSCHEDPARAM(3P)OSIX Programmer's ManuPaTlHREAD_ATTR_GETSCHEDPARAM(3)



PROLOG
       This manual page is part of the POSIX Programmer's Manual.  The OS
       implementation of this interface may differ (consult the corresponding
       OS manual page for details of OS behavior), or the interface may not be
       implemented on OS.

NAME
       pthread_attr_getschedparam, pthread_attr_setschedparam -- get and set
       the schedparam attribute

SYNOPSIS
       #include <pthread.h>

       int pthread_attr_getschedparam(const pthread_attr_t *restrict attr,
           struct sched_param *restrict param);
       int pthread_attr_setschedparam(pthread_attr_t *restrict attr,
           const struct sched_param *restrict param);

DESCRIPTION
       The pthread__attr__getschedparam() and pthread__attr__setschedparam()
       functions, respectively, shall get and set the scheduling parameter
       attributes in the attr argument. The contents of the param structure
       are defined in the <sched.h> header. For the SCHED_FIFO and SCHED_RR
       policies, the only required member of param is sched__priority.

       For the SCHED_SPORADIC policy, the required members of the param
       structure are sched__priority, sched__ss__low__priority,
       sched__ss__repl__period, sched__ss__init__budget, and sched__ss__max__repl.  The
       specified sched__ss__repl__period must be greater than or equal to the
       specified sched__ss__init__budget for the function to succeed; if it is
       not, then the function shall fail. The value of sched__ss__max__repl shall
       be within the inclusive range [1,{SS_REPL_MAX}] for the function to
       succeed; if not, the function shall fail.  It is unspecified whether
       the sched__ss__repl__period and sched__ss__init__budget values are stored as
       provided by this function or are rounded to align with the resolution
       of the clock being used.

       The behavior is undefined if the value specified by the attr argument
       to pthread__attr__getschedparam() or pthread__attr__setschedparam() does
       not refer to an initialized thread attributes object.

RETURN VALUE
       If successful, the pthread__attr__getschedparam() and
       pthread__attr__setschedparam() functions shall return zero; otherwise, an
       error number shall be returned to indicate the error.

ERRORS
       The pthread__attr__setschedparam() function shall fail if:

       ENOTSUP
              An attempt was made to set the attribute to an unsupported
              value.

       The pthread__attr__setschedparam() function may fail if:

       EINVAL The value of param is not valid.

       These functions shall not return an error code of [EINTR].

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       After these attributes have been set, a thread can be created with the
       specified attributes using pthread__create().  Using these routines does
       not affect the current running thread.

RATIONALE
       If an implementation detects that the value specified by the attr
       argument to pthread__attr__getschedparam() or
       pthread__attr__setschedparam() does not refer to an initialized thread
       attributes object, it is recommended that the function should fail and
       report an [EINVAL] error.

FUTURE DIRECTIONS
       None.

SEE ALSO
       pthread__attr__destroy(), pthread__attr__getscope(),
       pthread__attr__getinheritsched(), pthread__attr__getschedpolicy(),
       pthread__create()

       The Base Definitions volume of POSIX.1-2017, <pthread.h>, <sched.h>

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1-2017, Standard for Information Technology --
       Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  In the event of any discrepancy between this version and the
       original IEEE and The Open Group Standard, the original IEEE and The
       Open Group Standard is the referee document. The original Standard can
       be obtained online at http://www.opengroup.org/unix/online.html .

       Any typographical or formatting errors that appear in this page are
       most likely to have been introduced during the conversion of the source
       files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .



IEEE/The Open Group                  2017        PTHREAD_ATTR_GETSCHEDPARAM(3)
