NAME

tt_pattern_callback_add − register a message-matching callback function

SYNOPSIS

#include <Tt/tt_c.h>
Tt_status tt_pattern_callback_add(Tt_pattern m,
Tt_message_callback f);

DESCRIPTION

The tt_pattern_callback_add() function registers a callback function that will be automatically invoked by tt_message_receive(3) whenever a message matches the pattern. 

The callback is defined in <Tt/tt_c.h>.  If the callback returns TT_CALLBACK_CONTINUE, other callbacks will be run; if no callback returns TT_CALLBACK_PROCESSED, tt_message_receive(3) returns the message.  If the callback returns TT_CALLBACK_PROCESSED, no further callbacks will be invoked for this event; tt_message_receive(3) does not return the message. 

The m argument is the opaque handle for the pattern involved in this operation. 

The f argument is the message callback to be run. 

RETURN VALUE

Upon successful completion, the tt_pattern_callback_add() function returns the status of the operation as one of the following Tt_status values:

TT_OK
The operation completed successfully.

TT_ERR_NOMP
The ttsession(1) process is not running and the ToolTalk service cannot restart it. 

TT_ERR_POINTER
The pointer passed does not point to an object of the correct type for this operation.

SEE ALSO

Tttt_c(5), tt_pattern_register(3), tt_message_receive(3). 

SunOS 5.5/SPARC  —  Last change: 11 May 1994