Patch #2240: Implement signal.setitimer and signal.getitimer.
diff --git a/Doc/library/signal.rst b/Doc/library/signal.rst
index e909992..e300c5a 100644
--- a/Doc/library/signal.rst
+++ b/Doc/library/signal.rst
@@ -39,12 +39,13 @@
* Some care must be taken if both signals and threads are used in the same
program. The fundamental thing to remember in using signals and threads
simultaneously is: always perform :func:`signal` operations in the main thread
- of execution. Any thread can perform an :func:`alarm`, :func:`getsignal`, or
- :func:`pause`; only the main thread can set a new signal handler, and the main
- thread will be the only one to receive signals (this is enforced by the Python
- :mod:`signal` module, even if the underlying thread implementation supports
- sending signals to individual threads). This means that signals can't be used
- as a means of inter-thread communication. Use locks instead.
+ of execution. Any thread can perform an :func:`alarm`, :func:`getsignal`,
+ :func:`pause`, :func:`setitimer` or :func:`getitimer`; only the main thread
+ can set a new signal handler, and the main thread will be the only one to
+ receive signals (this is enforced by the Python :mod:`signal` module, even
+ if the underlying thread implementation supports sending signals to
+ individual threads). This means that signals can't be used as a means of
+ inter-thread communication. Use locks instead.
The variables defined in the :mod:`signal` module are:
@@ -78,6 +79,36 @@
One more than the number of the highest signal number.
+
+.. data:: ITIMER_REAL
+
+ Decrements interval timer in real time, and delivers SIGALRM upon expiration.
+
+
+.. data:: ITIMER_VIRTUAL
+
+ Decrements interval timer only when the process is executing, and delivers
+ SIGVTALRM upon expiration.
+
+
+.. data:: ITIMER_PROF
+
+ Decrements interval timer both when the process executes and when the
+ system is executing on behalf of the process. Coupled with ITIMER_VIRTUAL,
+ this timer is usually used to profile the time spent by the application
+ in user and kernel space. SIGPROF is delivered upon expiration.
+
+
+The :mod:`signal` module defines one exception:
+
+.. exception:: ItimerError
+
+ Raised to signal an error from the underlying :func:`setitimer` or
+ :func:`getitimer` implementation. Expect this error if an invalid
+ interval timer or a negative time is passed to :func:`setitimer`.
+ This error is a subtype of :exc:`IOError`.
+
+
The :mod:`signal` module defines the following functions:
@@ -110,6 +141,29 @@
:manpage:`signal(2)`.)
+.. function:: setitimer(which, seconds[, interval])
+
+ Sets given itimer (one of :const:`signal.ITIMER_REAL`,
+ :const:`signal.ITIMER_VIRTUAL` or :const:`signal.ITIMER_PROF`) especified
+ by *which* to fire after *seconds* (float is accepted, different from
+ :func:`alarm`) and after that every *interval* seconds. The interval
+ timer specified by *which* can be cleared by setting seconds to zero.
+
+ The old values are returned as a tuple: (delay, interval).
+
+ Attempting to pass an invalid interval timer will cause a
+ :exc:`ItimerError`.
+
+ .. versionadded:: 2.6
+
+
+.. function:: getitimer(which)
+
+ Returns current value of a given itimer especified by *which*.
+
+ .. versionadded:: 2.6
+
+
.. function:: set_wakeup_fd(fd)
Set the wakeup fd to *fd*. When a signal is received, a ``'\0'`` byte is
@@ -124,7 +178,6 @@
exception to be raised.
-
.. function:: siginterrupt(signalnum, flag)
Change system call restart behaviour: if *flag* is :const:`False`, system calls