SL_CHANNEL_QUIESCE_REQ primitive

Purpose

Request the signaling process to quiesce the specified channel for calls.

Requirement

Mandatory for common channel signaling processes. The primitive is not used by exchange data link signaling processes.

Library

The signaling interface library (libsl.a).

C syntax

typedef struct {
                SL_ID id;
                int iseq_no;
                pid_t pidCHP;
                SL_PRIMITIVE_TYPE Command;
                SL_REQUEST_PARM_ST Parms;
} SL_REQUEST_ST;
...
typedef union {
...
                struct _channel_quiesce_request_st{
                    size_t sizetLength;
                    int iChannelNo;
                    int iVpackNo;
                } channel_quiesce_request_st;
...
} SL_REQUEST_PARM_ST;

Description

The SL_CHANNEL_QUIESCE_REQ primitive is sent by the system manager to the signaling process to quiesce the specified channel. Quiescing a channel is a way of disabling the channel gracefully, no new calls are established, and when the current call is cleared, then the channel is disabled.

The SL_CHANNEL_QUIESCE_REQ primitive can be issued only if the channel is in state SL_CHANNEL_STATE_ENABLED. It changes the channel state to SL_CHANNEL_STATE_QUIESCING; calls in progress are not cleared. The signaling process should not use a channel that is in state SL_CHANNEL_STATE_QUIESCING for new calls.

After all calls on the channel have been cleared, either by the network or the channel process, the signaling process issues SL_CHANNEL_QUIESCE_CNF with a ReplyCode of SL_REPLY_SUCCESS, and changes the channel state to SL_CHANNEL_STATE_DISABLED; the channel can no longer be used to make or receive calls.

If the signaling process replies unsuccessfully to this primitive, the system manager logs an error, reporting that the signaling process has failed, or that it received a non-zero return code. The signaling process should log the reason for the failure, and diagnostic information, if it is available.

Corresponding state table action

None.

Corresponding user interface action

This primitive is issued by the System Monitor in response to the Quiesce button on the Channel Out of Service window.

Parameters

id: Eye-catcher that identifies the structure as containing a request primitive. Must be set to SLID_REQUEST_ST.
iseq_no: The sequence number of the primitive. This field must be set to 0 when the primitive is sent to Blueworx Voice Response; the actual sequence number is allocated by Blueworx Voice Response, and is available to the sender on return from sl_send_request(). The field is set when the primitive is received from Blueworx Voice Response by the signaling process.
pidCHP: The process id of the sending process. The signaling process should use this value to set the pidCHP field of the corresponding SL_CHANNEL_QUIESCE_CNF primitive.
Command.id: The primitive that the structure contains. Must be set to SL_CHANNEL_QUIESCE_REQ.
Parms.channel_quiesce_request_st.sizetLength: Must be set to sizeof(struct _channel_quiesce_request_st).
Parms.channel_quiesce_request_st.iChannelNo: Identifies the channel to quiesce.
Parms.channel_quiesce_request_st.iVpackNo: Identifies the trunk on which the channel is located.