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diff --git a/posix_users/clock.rst b/posix_users/clock.rst deleted file mode 100644 index e3387e7..0000000 --- a/posix_users/clock.rst +++ /dev/null @@ -1,341 +0,0 @@ -.. comment SPDX-License-Identifier: CC-BY-SA-4.0 - -.. COMMENT: This is the chapter from the RTEMS POSIX 1003.1b API User's Guide that -.. COMMENT: documents the services provided by the timer @c manager. - -Clock Manager -############# - -Introduction -============ - -The clock manager provides services two primary classes of services. The first -focuses on obtaining and setting the current date and time. The other category -of services focus on allowing a thread to delay for a specific length of time. - -The directives provided by the clock manager are: - -- clock_gettime_ - Obtain Time of Day - -- clock_settime_ - Set Time of Day - -- clock_getres_ - Get Clock Resolution - -- sleep_ - Delay Process Execution - -- usleep_ - Delay Process Execution in Microseconds - -- nanosleep_ - Delay with High Resolution - -- gettimeofday_ - Get the Time of Day - -- time_ - Get time in seconds - -Background -========== - -There is currently no text in this section. - -Operations -========== - -There is currently no text in this section. - -Directives -========== - -This section details the clock manager's directives. A subsection is dedicated -to each of this manager's directives and describes the calling sequence, -related constants, usage, and status codes. - -.. _clock_gettime: - -clock_gettime - Obtain Time of Day ----------------------------------- -.. index:: clock_gettime -.. index:: obtain time of day - -**CALLING SEQUENCE:** - -.. code-block:: c - - #include <time.h> - int clock_gettime( - clockid_t clock_id, - struct timespec *tp - ); - -**STATUS CODES:** - -On error, this routine returns -1 and sets ``errno`` to one of the following: - -.. list-table:: - :class: rtems-table - - * - ``EINVAL`` - - The tp pointer parameter is invalid. - * - ``EINVAL`` - - The clock_id specified is invalid. - -**DESCRIPTION:** - -**NOTES:** - -NONE - -.. _clock_settime: - -clock_settime - Set Time of Day -------------------------------- -.. index:: clock_settime -.. index:: set time of day - -**CALLING SEQUENCE:** - -.. code-block:: c - - #include <time.h> - int clock_settime( - clockid_t clock_id, - const struct timespec *tp - ); - -**STATUS CODES:** - -On error, this routine returns -1 and sets ``errno`` to one of the following: - -.. list-table:: - :class: rtems-table - - * - ``EINVAL`` - - The tp pointer parameter is invalid. - * - ``EINVAL`` - - The clock_id specified is invalid. - * - ``EINVAL`` - - The contents of the tp structure are invalid. - -**DESCRIPTION:** - -**NOTES:** - -NONE - -.. _clock_getres: - -clock_getres - Get Clock Resolution ------------------------------------ -.. index:: clock_getres -.. index:: get clock resolution - -**CALLING SEQUENCE:** - -.. code-block:: c - - #include <time.h> - int clock_getres( - clockid_t clock_id, - struct timespec *res - ); - -**STATUS CODES:** - -On error, this routine returns -1 and sets ``errno`` to one of the following: - -.. list-table:: - :class: rtems-table - - * - ``EINVAL`` - - The res pointer parameter is invalid. - * - ``EINVAL`` - - The clock_id specified is invalid. - -**DESCRIPTION:** - -**NOTES:** - -If ``res`` is ``NULL``, then the resolution is not returned. - -.. _sleep: - -sleep - Delay Process Execution -------------------------------- -.. index:: sleep -.. index:: delay process execution - -**CALLING SEQUENCE:** - -.. code-block:: c - - #include <unistd.h> - unsigned int sleep( - unsigned int seconds - ); - -**STATUS CODES:** - -This routine returns the number of unslept seconds. - -**DESCRIPTION:** - -The ``sleep()`` function delays the calling thread by the specified number of -``seconds``. - -**NOTES:** - -This call is interruptible by a signal. - -.. _usleep: - -usleep - Delay Process Execution in Microseconds ------------------------------------------------- -.. index:: usleep -.. index:: delay process execution -.. index:: delay process execution -.. index:: usecs delay process execution -.. index:: microsecond delay process execution - -**CALLING SEQUENCE:** - -.. code-block:: c - - #include <time.h> - useconds_t usleep( - useconds_t useconds - ); - -**STATUS CODES:** - -This routine returns the number of unslept seconds. - -**DESCRIPTION:** - -The ``sleep()`` function delays the calling thread by the specified number of -``seconds``. - -The ``usleep()`` function suspends the calling thread from execution until -either the number of microseconds specified by the ``useconds`` argument has -elapsed or a signal is delivered to the calling thread and its action is to -invoke a signal-catching function or to terminate the process. - -Because of other activity, or because of the time spent in processing the call, -the actual length of time the thread is blocked may be longer than the amount -of time specified. - -**NOTES:** - -This call is interruptible by a signal. - -The Single UNIX Specification allows this service to be implemented using the -same timer as that used by the ``alarm()`` service. This is *NOT* the case for -*RTEMS* and this call has no interaction with the ``SIGALRM`` signal. - -.. _nanosleep: - -nanosleep - Delay with High Resolution --------------------------------------- -.. index:: nanosleep -.. index:: delay with high resolution - -**CALLING SEQUENCE:** - -.. code-block:: c - - #include <time.h> - int nanosleep( - const struct timespec *rqtp, - struct timespec *rmtp - ); - -**STATUS CODES:** - -On error, this routine returns -1 and sets ``errno`` to one of the following: - -.. list-table:: - :class: rtems-table - - * - ``EINTR`` - - The routine was interrupted by a signal. - * - ``EAGAIN`` - - The requested sleep period specified negative seconds or nanoseconds. - * - ``EINVAL`` - - The requested sleep period specified an invalid number for the nanoseconds - field. - -**DESCRIPTION:** - -**NOTES:** - -This call is interruptible by a signal. - -.. _gettimeofday: - -gettimeofday - Get the Time of Day ----------------------------------- -.. index:: gettimeofday -.. index:: get the time of day - -**CALLING SEQUENCE:** - -.. code-block:: c - - #include <sys/time.h> - #include <unistd.h> - int gettimeofday( - struct timeval *tp, - struct timezone *tzp - ); - -**STATUS CODES:** - -On error, this routine returns -1 and sets ``errno`` as appropriate. - -.. list-table:: - :class: rtems-table - - * - ``EPERM`` - - ``settimeofdat`` is called by someone other than the superuser. - * - ``EINVAL`` - - Timezone (or something else) is invalid. - * - ``EFAULT`` - - One of ``tv`` or ``tz`` pointed outside your accessible address space - -**DESCRIPTION:** - -This routine returns the current time of day in the ``tp`` structure. - -**NOTES:** - -Currently, the timezone information is not supported. The ``tzp`` argument is -ignored. - -.. _time: - -time - Get time in seconds --------------------------- -.. index:: time -.. index:: get time in seconds - -**CALLING SEQUENCE:** - -.. code-block:: c - - #include <time.h> - int time( - time_t *tloc - ); - -**STATUS CODES:** - -This routine returns the number of seconds since the Epoch. - -**DESCRIPTION:** - -``time`` returns the time since 00:00:00 GMT, January 1, 1970, measured in -seconds - -If ``tloc`` in non null, the return value is also stored in the memory pointed -to by ``t``. - -**NOTES:** - -NONE |