srv_wakeup

Description

Enable sleeping threads to run.

Syntax

CS_RETCODE srv_wakeup(sleepeventp, wakeflags,
                   reserved1, reserved2)

CS_VOID          *sleepeventp;
CS_INT             wakeflags;
CS_VOID          *reserved1;
CS_VOID          *reserved2;

Parameters

sleepeventp: A generic void pointer to the operating system event on which the threads are sleeping.

wakeflags

A bit mask that modifies the way that srv_wakeup behaves. If no bits are set, the default action is to wake up all threads sleeping on the event.The bits can be OR’d together. The following table describes the legal values for wakeflags:

**Table 3-147: Values for wakeflags (srv_wakeup)**
Value	Description
SRV_M_WAKE_INTR	The call to srv_wakeup is from interrupt level code. Failure to use this flag when calling srv_wakeup from interrupt level code can cause the Open Server application to behave erratically. Using this flag at non-interrupt level will cause the Open Server application to behave erratically. This flag must be used when srv_wakeup is used in VMS AST routines.
SRV_M_WAKE_FIRST	Only the first thread sleeping on the event is made runnable.
SRV_M_WAKE_ALL	Wake up all threads sleeping on the event.

reserved1: This parameter is not used. It must be set to (CS_VOID*)0.

reserved2: This parameter is not used. It must be set to (CS_VOID*)0.

Returns

srv_wakeup returns CS_FAIL if no sleeping threads were found for the event or if any parameters were in error. If one or more sleeping threads were found, srv_wakeup returns CS_SUCCEED.

**Table 3-148: Return values (srv_wakeup)**
Returns	To indicate
CS_SUCCEED	One or more sleeping threads were found and enabled to run.
CS_FAIL	The routine failed, or no sleeping threads were found.

Examples

Example 1

#include    <ospublic.h>

/*

** Local Prototype.

*/

CS_RETCODE ex_srv_wakeup PROTOTYPE((

CS_VOID    *sep

));

/*

** EX_SRV_WAKEUP

**

**    Example routine using srv_wakeup to make all Open Server

 **    threads, which were previously sleeping on the specified

 **    sleep event, runnable again.

**

** Arguments:

**    sep    A generic void pointer, which was used previously in

 **           calls to srv_sleep to suspend threads.

**

** Returns:

**    CS_SUCCEED    Threads sleeping on the specified sleep event

 **                  are runnable again.

**    CS_FAIL       An error was detected.

*/

CS_RETCODE      ex_srv_wakeup(sep)

CS_VOID         *sep;

/*

      ** Wake up threads for the specified sleep event, passing

       ** zero for reserved fields.

*/

      if (srv_wakeup(sep, (CS_INT)SRV_M_WAKE_ALL,

           (CS_VOID*)0, (CS_VOID*)0) != CS_SUCCEED)

           return(CS_FAIL);

     return(CS_SUCCEED);

Usage

srv_wakeup wakes threads that are sleeping on sleepevent.
When srv_wakeup is called from interrupt level code, the actual wakeup is deferred until the scheduler next executes.
srv_wakeup cannot be used in a SRV_START handler.
When writing preemptive mode programs with Open Server, srv_wakeup and srv_sleep must use platform-dependent mutexes. See the Open Client and Open Server Programmer’s Supplement for your platform for an example of preemptive scheduling.