Mainframe, MVS and zOS Discussion

One can get the last record if we used "WRITE FROM" from some WS variable. But when you use only WRITE, the data is no longer available to the program because the pointer to the i/o buffer has been moved. If a programmer refers to the record-area after the WRITE (not WRITE FROM), the result is unpredictable - is this understading correct about WRITE and WRITE FROM?

From the Manual

http://publibz.boulder.ibm.com/cgi-bin/ ... 0821081020

FROM phrase The result of the execution of the WRITE statement with the FROM identifier-1 phrase is equivalent to the execution of the following statements in the order specified:
MOVE identifier-1 TO record-name-1.
WRITE record-name-1.
The MOVE is performed according to the rules for a MOVE statement without the CORRESPONDING phrase.

If a programmer refers to the record-area after the WRITE (not WRITE FROM), the result is unpredictable

This understanding is wrong -- attempting to access the record-area after a WRITE or WRITE FROM will yield unpredictable results, not just after the WRITE. With WRITE FROM, you can get to the last record because it is still in WORKING-STORAGE, not the record-area.

Thanks Robert. I've to get used to the terminology better.

Thanks.

I've to get used to the terminology better.

One of the Most Important things to do. . .

Terminology is Critical for understanding and quite often it is the terminology used that causes confusion.

We will help with terminology when we can. It is quit all right to ask when noe sure.