User`s guide

4: Record Transfer Interface (BSCRTI)
DC 900-1406E 87
4.7 BSCWRIT Procedure
This procedure can be called only after the ICP has been assigned (see the BSCASL pro-
cedure, Section 4.1 on page 74).
The caller has total responsibility for insertion of record separators or transparent 2780
count characters, and ensuring that the total ICP writeblock size does not exceed the
value of the
DEFAULT /BUFSIZE option (default is 1024).
To increase efficiency, BSCWRIT uses a write rotate window of two, allowing a maxi-
mum of two outstanding data acks at any one time. This significantly increases
throughput compared to waiting for the data acknowledgment after every write to the
ICP. To take advantage of this feature, applications calling BSCWRIT should use
action
parameters 1, 3, or 8 for the ETB blocks.
Calling Sequence
ReturnCode = BSCWRIT (rdblock, recbuf, action, dtime, dak)
Procedures Called
BSCRESET and BSCFWY
Functions
1. Transfers record in buffer (recbuf) to the ICP writeblock. BSCWRIT does not
add record separator or count characters.
2. Based on
action, sends the appropriate type of block to the ICP and waits for
ACK if appropriate.
3. Calls BSCRESET after handling the ETX block or if a fatal error or timeout
(
dtime) occurs.