From b3f3dd123c181fe851f0a9756bed7acd4ba4ef7d Mon Sep 17 00:00:00 2001 From: patacongo Date: Sun, 13 Jan 2013 18:53:00 +0000 Subject: Use SIGCHLD with waitpid(); implemented wait() and waitid() git-svn-id: http://svn.code.sf.net/p/nuttx/code/trunk@5515 42af7a65-404d-4744-a932-0658087f49c3 --- nuttx/Documentation/NuttX.html | 8 +- nuttx/Documentation/NuttxPortingGuide.html | 10 +- nuttx/Documentation/NuttxUserGuide.html | 181 +++++++++++++++++++++++++++-- 3 files changed, 179 insertions(+), 20 deletions(-) (limited to 'nuttx/Documentation') diff --git a/nuttx/Documentation/NuttX.html b/nuttx/Documentation/NuttX.html index f6e9a41ba..22651de79 100644 --- a/nuttx/Documentation/NuttX.html +++ b/nuttx/Documentation/NuttX.html @@ -286,7 +286,7 @@

  • Easily extensible to new processor architectures, SoC architecture, or board architectures. - A Porting Guide is available. + A Porting Guide is available.

    • @@ -536,7 +536,7 @@

    -

  • Power management sub-system.
    • +
  • Power management sub-system.

    • @@ -1009,7 +1009,7 @@ This configuration file contains a long list of settings that control what is built into NuttX and what is not. There are hundreds of such settings - (see the NuttX Porting Guide + (see the NuttX Porting Guide for a partial list that excludes platform specific settings). These many, many configuration options allow NuttX to be highly tuned to meet size requirements. @@ -3837,7 +3837,7 @@ pascal-3.0 2011-05-15 Gregory Nutt <gnutt@nuttx.org> - Porting Guide + Porting Guide diff --git a/nuttx/Documentation/NuttxPortingGuide.html b/nuttx/Documentation/NuttxPortingGuide.html index 0b67eddb7..fec7106b0 100644 --- a/nuttx/Documentation/NuttxPortingGuide.html +++ b/nuttx/Documentation/NuttxPortingGuide.html @@ -12,7 +12,7 @@

    NuttX RTOS Porting Guide

    -

    Last Updated: January 12, 2013

    +

    Last Updated: January 13, 2013

    @@ -4482,7 +4482,8 @@ build
  • CONFIG_SCHED_HAVE_PARENT: Remember the ID of the parent thread when a new child thread is created. - This support enables a few minor features (such as SIGCHLD) and slightly increases the size of the Task Control Block (TCB) of every task to hold the ID of the parent thread. + This support enables some additional features (such as SIGCHLD) and modifies the behavior of other interfaces. + For example, it makes waitpid() more standards complete by restricting the waited-for tasks to the children of the caller. Default: disabled.
  • @@ -4601,10 +4602,11 @@ build CONFIG_SCHED_LPWORKPERIOD: How often the lower priority worker thread checks for work in units of microseconds. Default: 50*1000 (50 MS).
  • - CONFIG_SCHED_LPWORKSTACKSIZE - The stack size allocated for the lower priority worker thread. Default: CONFIG_IDLETHREAD_STACKSIZE. + CONFIG_SCHED_LPWORKSTACKSIZE: The stack size allocated for the lower priority worker thread. Default: CONFIG_IDLETHREAD_STACKSIZE.
  • - CONFIG_SCHED_WAITPID: Enables the waitpid() API + CONFIG_SCHED_WAITPID: Enables the waitpid() interface in a default, non-standard mode (non-standard in the sense that the waited for PID need not be child of the caller). + If SCHED_HAVE_PARENT is also defined, then this setting will modify the behavior or waitpid() (making more spec compliant) and will enable the waitid() and waitp() interfaces as well.
  • CONFIG_SCHED_ATEXIT: Enables the atexit() API diff --git a/nuttx/Documentation/NuttxUserGuide.html b/nuttx/Documentation/NuttxUserGuide.html index c6eabd29a..3cfb63f11 100644 --- a/nuttx/Documentation/NuttxUserGuide.html +++ b/nuttx/Documentation/NuttxUserGuide.html @@ -13,7 +13,7 @@

    NuttX Operating System

    User's Manual

    by

    Gregory Nutt

    -

    Last Updated: January 11, 2013

    +

    Last Updated: January 13, 2013

    @@ -1776,8 +1776,10 @@ priority of the calling task is returned.

    Task synchronization interfaces

    2.3.1 sched_lock

    @@ -1886,10 +1888,12 @@ on this thread of execution. Description:

    - The following discussion is a general description of the waitpid() interface. - However, as of this writing, the implementation of waitpid() is fragmentary (but usable). - It simply supports waiting for any task to complete execution. - NuttX does not support any concept of parent/child processes or of process groups nor signals related to child processes (SIGCHLD). + The following discussion is a general description of the waitpid() interface. + However, as of this writing, the implementation of waitpid() is incomplete (but usable). + If CONFIG_SCHED_HAVE_PARENT is defined, waitpid() will be a little more compliant to specifications. + Without CONFIG_SCHED_HAVE_PARENT, waitpid() simply supports waiting for any task to complete execution. + With CONFIG_SCHED_HAVE_PARENT, waitpid() will use SIGCHLD and can, therefore, wait for any child of the parent to complete. + The implementation is incomplete in either case, however: NuttX does not support any concept of process groups. Nor does NuttX retain the status of exited tasks so if waitpid() is called after a task has exited, then no status will be available. The options argument is currently ignored.
    @@ -2038,7 +2042,158 @@ on this thread of execution. Comparable to the POSIX interface of the same name, but the implementation is incomplete (as detailed above).

    -

    2.3.5 atexit

    +

    2.3.5 waitid

    • +

    +Function Prototype: +

    +    #include <sys/wait.h>
+    #ifdef CONFIG_SCHED_HAVE_PARENT
+    int waitid(idtype_t idtype, id_t id, FAR siginfo_t *info, int options);
+    #endif
+
    +

    + Description: +

    +
    + The following discussion is a general description of the waitid() interface. + However, as of this writing, the implementation of waitid() is incomplete (but usable). + If CONFIG_SCHED_HAVE_PARENT is defined, waitid() will be a little more compliant to specifications. + waitpid() simply supports waiting a specific child task (P_PID or for any child task P_ALL to complete execution. + SIGCHLD is used. + The implementation is incomplete in either case, however: NuttX does not support any concept of process groups. + Nor does NuttX retain the status of exited tasks so if waitpid() is called after a task has exited, then no status will be available. + The options argument is currently ignored. +
    +

    + The waitid() function suspends the calling thread until one child of the process containing the calling thread changes state. + It records the current state of a child in the structure pointed to by info. + If a child process changed state prior to the call to waitid(), waitid() returns immediately. + If more than one thread is suspended in wait() or waitpid() waiting termination of the same process, exactly one thread will return the process status at the time of the target process termination +

    +

    + The idtype and id arguments are used to specify which children waitid() will wait for. +

    +

    +

    +

    + The options argument is used to specify which state changes waitid() will will wait for. + It is formed by OR-ing together one or more of the following flags: +

    + + The info argument must point to a siginfo_t structure. + If waitid() returns because a child process was found that satisfied the conditions indicated by the arguments idtype and options, then the structure pointed to by info will be filled in by the system with the status of the process. + The si_signo member will always be equal to SIGCHLD. +

    +

    + Input Parameters: + See the description above. +

    +

    + Returned Value: + If waitid() returns due to the change of state of one of its children, 0 is returned. + Otherwise, -1 is returned and errno is set to indicate the error. +

    +

    + The waitid() function will fail if: +

    + +

    + Assumptions/Limitations: +

    + POSIX Compatibility: + Comparable to the POSIX interface of the same name, but the implementation is incomplete (as detailed in the description above). +

    + +

    2.3.6 wait

    +

    +Function Prototype: +

    +    #include <sys/wait.h>
+    #ifdef CONFIG_SCHED_HAVE_PARENT
+    pid_t wait(FAR int *stat_loc);
+    #endif
+
    +

    + Description: +

    +
    + The following discussion is a general description of the wait() interface. + However, as of this writing, the implementation of wait() is incomplete (but usable). + wait() is based on waitpaid(). + See the description of waitpaid() for further information. +
    +

    + The wait() function will suspend execution of the calling thread until status information for one of its terminated child processes is available, or until delivery of a signal whose action is either to execute a signal-catching function or to terminate the process. + If more than one thread is suspended in wait() awaiting termination of the same process, exactly one thread will return the process status at the time of the target process termination. + If status information is available prior to the call towait(), return will be immediate. +

    +

    + The waitpid() function will behave identically to wait(), if its pid argument is (pid_t)-1 and the options argument is 0. + Otherwise, its behavior will be modified by the values of the pid and options arguments. +

    +

    + Input Parameters: +

    + +

    + Returned Value: + See the values returned by waitpaid(). +

    +

    + Assumptions/Limitations: +

    + POSIX Compatibility: + Comparable to the POSIX interface of the same name, but the implementation is incomplete (as detailed in the description waitpaid()). +

    + +

    2.3.7 atexit

    Function Prototype: @@ -2077,7 +2232,7 @@ on this thread of execution.

  • atexit() functions are not inherited when a new task is created.
    • -

    2.3.6 on_exit

    +

    2.3.8 on_exit

    Function Prototype: @@ -9023,9 +9178,9 @@ notify a task when a message is available on a queue.

  • pipe
  • poll
  • poll.h
    • +
  • posix_spawn
    • -
  • posix_spawn
  • posix_spawn_file_actions_addclose
  • posix_spawn_file_actions_adddup2
  • posix_spawn_file_actions_addopen
    • @@ -9107,10 +9262,10 @@ notify a task when a message is available on a queue.
  • recv
  • recvfrom
  • rename
    • - -
  • rmdir
  • rewinddir
    • + +
  • ROM disk driver
  • ROMFS
  • sched_getparam
    • @@ -9183,6 +9338,8 @@ notify a task when a message is available on a queue.
  • vfprintf
  • vprintf
  • vsprintf
    • +
  • wait
    • +
  • waitid
  • waitpid
  • Watchdog Timer Interfaces
  • wd_cancel
    • -- cgit v1.2.3