Error Propagation

ToolTalk functions that accept pointers always check the pointer passed in and return TT_ERR_POINTER if the pointer is an error value. This check allows you to combine calls in reasonable ways without checking the value of the pointer for every single call.

In , a message is created, filled in, and sent. If tt_message_create fails, an error object is assigned to m, and all the tt_message_xxx_set and tt_message_send calls fail. To detect the error without checking between each call, you only need to check the return code from tt_message_send.

Example 14-4 Error Checking

Tt_message m;

m=tt_message_create();
tt_message_op_set(m,”OP”);
tt_message_address_set(m,TT_PROCEDURE);
tt_message_scope_set(m,TT_SESSION);
tt_message_class_set(m,TT_NOTICE);
tt_rc=tt_message_send(m);
if (tt_rc!=TT_OK)...