TN3270 Server Manual

CRT Communication Protocol

TN3270 Server Manual—424097-001

5-6

SETMODE Function 59 Procedure

A SETMODE function 59 procedure returns the actual count of bytes read as a result of

a CONTROL 22 operation (two-step READ request) completion.

filenumber

INT:value

is the file to receive the SETMODE function.

INT:value

is the SETMODE number for obtaining the actual count of the bytes read.

last-params

INT .ref:2

is a value that must be provided. It returns:

last-params[0]

is the actual number of bytes read.

last-params[1]

is a 0 (zero).

The parameter positions normally used for param1 and param2 of the SETMODE

procedure are not used in a SETMODE 59 procedure. Do not provide these parameters.

If you do, Error 2 (invalid operation attempted) is returned. Error 26 is returned if the

subdevice has no outstanding two-step READ requests completed or if the SETMODE

requester is not the two-step READ requester.

Example

The following is an example of the application request sequence using a two-step READ

and a SETMODE 59:

CALL SETMODE (filenumber, 59, , , last-params);

CALL CONTROL (T1,22,500);

CALL AWAITIO (T1, ... );

posts a 500-byte READ to T1 and waits

for completion.

CALL SETMODE (T1,59,,,PARAMS);

the READ request has completed; it gets

the actual size.

CALL READ(T1,BUFFER,PARAMS[0]);

the READ request has completed with the

actual byte size instead of 500.