ttdt_message_accept(3) ToolTalk Functions ttdt_message_accept(3)NAMEttdt_message_accept - accept a contract to handle a ToolTalk request
SYNOPSIS
#include <Tt/tttk.h>
Tt_pattern *ttdt_message_accept(Tt_message contract,
Ttdt_contract_cb cb,
void *clientdata,
Widget shell,
int accept,
int sendStatus);
DESCRIPTION
The ttdt_message_accept() function registers in the default session for
TT_HANDLER-addressed requests:
(1) Get_Geometry, Set_Geometry, Get_Iconified, Set_Iconified,
Get_Mapped, Set_Mapped, Raise, Lower, Get_XInfo, Set_XInfo
(2) Pause, Resume
(3) Quit, Get_Status
If the shell argument is not NULL, the ToolTalk service handles mes‐
sages in (1) transparently; otherwise, it treats them like messages in
(3).
If shell is non-NULL and cb is NULL, then the ToolTalk service handles
messages in (2) transparently by passing shell and the appropriate
boolean value to XtSetSensitive(3X). If cb is NULL, then the ToolTalk
service treats messages in (2) like (3).
If cb is not NULL, ttdt_message_accept() passes messages in (3) to the
cb callback; otherwise it fails with TT_DESKTOP_ENOTSUP.
If accept is True, ttdt_message_accept() calls tt_message_accept(3)
with a contract argument. If contract has a returned value from
tt_message_status() of TT_WRN_START_MESSAGE, it is the message that
caused the tool to be started. The tool should join any scopes it
wants to serve before accepting contract, so that it will receive any
other messages already dispatched to its ptype. Otherwise, those mes‐
sages will cause other instances of the ptype to be started. If that
is in fact desired (for example, because the tool can only service one
message at a time), then the tool should undeclare its ptype while it
is busy.
If sendStatus is True, ttdt_message_accept() sends a Status notice to
the requester, using the arguments (if any) passed to ttdt_open().
RETURN VALUE
Upon successful completion, the ttdt_message_accept() function returns
a null-terminated array of Tt_pattern, and associates this array with
contract; otherwise, it returns an error pointer. The application can
use tt_ptr_error(3) to extract one of the following Tt_status values
from the returned handle:
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 cor‐
rect type for this operation.
TT_ERR_UNIMP
The ttsession(1) for the default session is of a version
that does not support tt_message_accept(). If contract is a
TT_WRN_START_MESSAGE, messages to the tool's ptype will
remain blocked until contract is rejected, replied to, or
failed.
APPLICATION USAGE
The ttdt_message_accept() function is what a tool calls when it wants
to accept responsibility for handling (that is, failing or rejecting) a
request.
If contract is destroyed by tttk_message_destroy(3), then the patterns
will also be destroyed. Otherwise, the caller is responsible for iter‐
ating over the array and destroying each pattern.
EXAMPLES
See ttdt_session_join(3) for an example of a Ttdt_contract_cb callback
that can be used with ttdt_message_accept().
SEE ALSOtttk(5), ttdt_open(3), ttmedia_ptype_declare(3), tt_ptype_declare(3),
ttdt_session_join(3), ttdt_file_join(3), tt_ptype_undeclare(3),
tt_ptype_undeclare(3), XtSetSensitive(3X).
ToolTalk 1.3 1 March 1996 ttdt_message_accept(3)
