From 5897a8e4c5f23e77255b6f57fb1d7afa1f0bce34 Mon Sep 17 00:00:00 2001 From: Jeff Hill Date: Thu, 25 Apr 2002 18:06:35 +0000 Subject: [PATCH] clarified monitor subscription interface --- src/ca/CAref.html | 27 +++++++++++++++++++++------ 1 file changed, 21 insertions(+), 6 deletions(-) diff --git a/src/ca/CAref.html b/src/ca/CAref.html index 5b9f78d54..864827f53 100644 --- a/src/ca/CAref.html +++ b/src/ca/CAref.html @@ -982,7 +982,10 @@ resulting from the initiating call back function is invoked indicating bad status. If the channel disconnects before a put callback request can be completed, then the client's call back function is called with bad status, but this does not gaurantee -that the server did not receive and process the request before it +that the server did not receive and process the request before the +disconnect.

+ +

All of these functions return ECA_DISCONN if the channel is currently disconnected.

All put requests are accumulated (buffered) and not forwarded to the IOC @@ -1043,6 +1046,8 @@ This allows several requests to be efficiently combined into one message.

ECA_ALLOCMEM - Unable to allocate memory

+

ECA_DISCONN - Channel is disconnected

+

See Also

ca_flush_io() @@ -1076,6 +1081,9 @@ values requested by ca_get_callback. If the channel disconnects before a get callback request can be completed, then the clients call back function is called with bad status. +

All of these functions return ECA_DISCONN if the channel is currently +disconnected.

+

All get requests are accumulated (buffered) and not forwarded to the IOC until one of ca_flush_io, ca_pend_io, ca_pend_event, or ca_sg_pend are called. This allows several requests to be efficiently sent over the network @@ -1135,6 +1143,8 @@ in one message.

ECA_ALLOCMEM - Unable to allocate memory

+

ECA_DISCONN - Channel is disconnected

+

See Also

ca_pend_io() @@ -1166,13 +1176,18 @@ be invoked whenever A significant change can be a change in the process variable's value, alarm status, or alarm severity. In the process control function block database the deadband field determines the magnitude of a significant change for for the -process variable's value.

+process variable's value. Each call to this function consumes resources in +the client library and potentially a CA server until one of ca_clear_channel +or ca_clear_event is called.

Subscriptions may be installed or canceled against both connected and -disconnected channels. The specified USERFUNC is always called once -immediately after establishing each new connection with the process variable -or immediately from within ca_add_event() if the client and server share the -same address space.

+disconnected channels. The specified USERFUNC is called once immediately +after the subscription is installed with the process variable's current state +if the process variable is connected. Otherwise, the specified USERFUNC is +called immediately after establishing a connection (or reconnection) with the +process variable. The specified USERFUNC is called immediately with the +process variable's current state from within ca_add_event() if the client and +the process variable share the same address space.

If a subscription is installed on a channel in a disconnected state then the requested count will be set to the native maximum element count of the