07-30-2003
Hi,
Thanks for your replay.
I'll try to be more clear -
1. i have created the Q as follow:
'o_qid = msgget(IPC_PRIVATE,IPC_CREAT|0777|IPC_EXCL|S_IRUSR|S_IWUSR);'
And worked with the Q as follow:
'msgsnd( qid, (void*)(&eventDataBuffer), MessageSize, 0) '
'qbytesread=msgrcv(qid, (void*)pMessage, max_msgsize, -MSGTYPE_MAX_APP_RANGE, 0)'
2. The Q has functioned OK for about an hour, where data was surely sent & received.
3. On a certain point, i could not send, nor receive from the Q.
The parameters on the Q where:
Qnum=0 (The number of messages currently outstanding on the
associated message queue.)
CBYTES= ~4k (The number of bytes in messages currently outstanding on the associated message queue.)
This is what i do not understand. How come there are no messages, and the Q inform me that the data size is greater than 0?
I hope i made more clear.
Thanks Again.
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LEARN ABOUT HPUX
tt_message_disposition
tt_message_disposition(library call) tt_message_disposition(library call)
NAME
tt_message_disposition -- retrieve the disposition attribute from a message
SYNOPSIS
#include <Tt/tt_c.h>
Tt_disposition tt_message_disposition(
Tt_message m);
DESCRIPTION
The tt_message_disposition function retrieves the disposition attribute from the specified message.
The m argument is the opaque handle for the message involved in this operation.
RETURN VALUE
Upon successful completion, the tt_message_disposition function returns a value that indicates whether an instance of the receiving process
should be started to receive the message immediately, or whether the message is to be queued until the receiving process is started at a
later time. The tt_message_disposition function returns one of the following Tt_disposition values:
TT_DISCARD
There is no receiver for this message. The message will be returned to the sender with the Tt_status field containing TT_FAILED.
TT_QUEUE Queue the message until a process of the proper ptype receives the message.
TT_START Attempt to start a process of the proper ptype if none is running.
TT_QUEUE+TT_START
Queue the message and attempt to start a process of the proper ptype if none is running.
The application can use tt_int_error(3) to extract one of the following Tt_status values from the Tt_disposition integer:
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
Tt/tt_c.h - Tttt_c(5), tt_int_error(3).
tt_message_disposition(library call)