srv_deletemsgq

Description

Delete a message queue.

Syntax

CS_RETCODE srv_deletemsgq(msgqnamep, msgqname_len,

              msgqid)

CS_CHAR       *msgqnamep;
CS_INT            msgqname_len;
SRV_OBJID     msgqid;

Parameters

msgqnamep: A pointer to the name of the message queue to delete. It is an error to attempt to delete a message queue that does not exist.

msgqname_len: The length of the name pointed to by msgqname. If the name is null terminated, msgqname_len can be set to CS_NULLTERM.

msgqid: A SRV_OBJID that specifies the identifier of message queue to delete.

Returns

**Table 3-32: Return values (srv_deletemsgq)**
Returns	To indicate
CS_SUCCEED	The routine completed successfully.
CS_FAIL	The routine failed.

Examples

Example 1

#include          <ospublic.h>

/*

 ** Local Prototype.

*/

CS_RETCODE      ex_srv_deletemsgq PROTOTYPE((

CS_CHAR         *msgqname,

CS_INT          msgqname_len,

SRV_OBJID msgqid

));

/*

 ** EX_SRV_DELETEMSGQ

**

**     Example routine using srv_deletemsgq to delete an Open

 **     Server message queue previously create by srv_createmsgq.

** This routine can be passed a value message queue name, or

 ** NULL,in which case the message queue identifier will be used.

**

** Arguments:

**  msgqname        The name of the message queue to delete. If

 **                  NULL, the msgqid is used.

 **  msgqname_len    The length of the name to which msgqname

 **                  points.

 **  msgqid          A SRV_OBJID that specifies the identifier of

 **                  the message queue to delete.

**

** Returns:

**

**    CS_SUCCEED    The message queue was successfully deleted.

**    CS_FAIL       An error was detected.

*/

CS_RETCODE      ex_srv_deletemsgq(msgqname, msgqname_len, msgqid)

CS_CHAR         *msgqname;

CS_INT          msgqname_len;

SRV_OBJID       msgqid;

/*

      ** Delete a message queue.

*/

     if (srv_deletemsgq(msgqname, msgqname_len, msgqid) !=

           CS_SUCCEED)

          return(CS_FAIL);

     return(CS_SUCCEED);

Usage

Message queues can be deleted by either name or ID. If msgqname is not NULL, the message queue name is used; otherwise, the message queue ID is used.

Unread messages in the queue are flushed before the queue is deleted. Threads waiting in srv_putmsgq wake up. srv_putmsgq returns CS_FAIL.

When a message queue is deleted, threads waiting for messages from the queue wake up with a CS_FAIL return value from srv_getmsgq, and srv_getmsgq’s infop argument is set to SRV_I_DELETED.

The SRV_S_NUMMSGQUEUES server property determines the number of message queues available to an Open Server application. Refer to “Server properties” for more information.
The SRV_S_MSGPOOL server property determines the number of messages available to an Open Server application at runtime. Refer to “Server properties” for more information.