TipcSrvConnSubjectSetSubscribe

Name

TipcSrvConnSubjectSetSubscribe — start or stop subscribing to a subject

Synopsis

T_BOOL TipcSrvConnSubjectSetSubscribe(srv, subject, subscribe_status) 
T_IPC_SRV srv; 
T_STR subject; 
T_BOOL subscribe_status; 

Arguments

srv — connection handle to RTserver

subject — name of the subject to set subscribe status for

subscribe_status — subscribe status

Return Values

TRUE if the subscribe status of the subject was successfully set, FALSE otherwise.

Diagnostics

If TipcSrvConnSubjectSetSubscribe fails, it returns FALSE and sets the global SmartSockets error number to one of:

Description

TipcSrvConnSubjectSetSubscribe sets whether or not this RTclient is subscribing to a subject. The subscribe status controls whether or not the RTclient receives messages published (sent) to that subject. If the subscribe status of subject is TRUE, then the RTclient receives messages with subject as their destination that are sent to RTserver. To determine if an RTclient is subscribing to a subject, use TipcSrvConnSubjectGetSubscribe.

TipcSrvConnSubjectSetSubscribe may attempt to automatically create a connection to RTserver. If RTclient has a warm connection to RTserver, TipcSrvConnSubjectSetSubscribe sets the subscribe status of the subject as if the RTclient were still connected to RTserver. See TipcSrvConnOpen for more information on automatic creation of connections and warm connections to RTserver.

There are a number of standard subjects available to all RTclients. See TipcSrvConnStdSubjectSetSubscribe for more information on these standard subjects.

To determine if an RTclient is subscribing to a subject, with or without load balancing information, use TipcSrvConnSubjectSetSubscribeLb.

Caution

TipcSrvConnSubjectSetSubscribe sends a SUBJECT_SET_SUBSCRIBE message to RTserver, but does not explicitly flush the message. See TipcSrvConnGetAutoFlushSize for more information on message buffering.

See Also

TipcMonClientSubscribeSetWatch, TipcMonSubjectSubscribeSetWatch, TipcSrvConnSubjectGetSubscribe, TipcSrvConnStdSubjectSetSubscribe, TipcSrvConnSubjectSetSubscribeLb

Examples

This example uses TipcSrvConnSubjectSetSubscribe to start subscribing to the subject /system/thermal:

if (!TipcSrvConnSubjectSetSubscribe(srv, "/system/thermal", TRUE)) 
{ 
  return;  /* error */ 
}