GDSX (Extended General Device Support) Manual

Service Routines
Extended General Device Support (GDSX) Manual—529931-001
8-69
SEND^ITC^MSG[X]
is a pointer to an FCB corresponding to the calling task’s ITC file or to some other
file to which the I/O is to be linked. At the time of call, this FCB must contain the
TCB address for the receiving task in fcb.lhaddr.
When a DEVICE^HANDLER task is sending a message to a LINE^HANDLER task
that it is configured for, obtain the FCB address for the DEVICE^HANDLER task’s
ITC file by indexing into FCBTBL, the FCB table, with the terminal file number.
The terminal file number is passed when the DEVICE^HANDLER task is created.
Then fcb.lhaddr will already be set to the TCB address of the LINE^HANDLER
task.
In the following cases, the FCB of the receiving task is obtained by calling
GET^ITC^FCB once:
•
A DEVICE^HANDLER task is sending a message to a LINE^HANDLER task
that it is not configured for
•
A DEVICE^HANDLER task is sending a message to another
DEVICE^HANDLER task
•
A LINE^HANDLER task is sending a message to a DEVICE^HANDLER task
•
A LINE^HANDLER task is sending a message to another LINE^HANDLER
task
The FCB returned by GET^ITC^FCB is used for fcb in subsequent calls to
SEND^ITC^MSG[X] to send a message to the receiving task.
message input
is a pointer to a buffer containing a message.
write-count input
INT:value
is the number of bytes to write.
read-count input
INT:value
is the number of bytes to read.
tag input
INT(32):value
is a tag, usually an IOCB address.
INT:ref (Use with SEND^ITC^MSG)
INT .EXT:ref (Use with SEND^ITC^MSGX)