Re: RPG Blocked Writes

On 08/06/2010, at 8:22 AM, Kurt Anderson wrote:

I have a file defined in a program as:

FFileA O A E K Disk

From my understanding, writes to this file should be blocked. However when I look at the I/O for the job, the I/O count and the RRN is always equal. For comparison, reading a file that's blocked has a lower I/O count than the current RRN.

Is this a matter of me not understanding the I/O screen (when looking at the job as it is running), or is this file actually writing a single record at a time?

According to this document, I feel that these writes should be blocked.
https://www-912.ibm.com/s_dir/slkbase.NSF/1ac66549a21402188625680b0002037e/d6738e1cd37e1f33862565c2007cef79?OpenDocument
"All high-level language programs (HLLs) use blocking at certain times and use single record I/O at other times, based on program specifications. Because blocking takes less system resources to perform a single I/O, a program that blocks performs better and uses less system resources. The default for the HLL uses record blocking if opening a file for output only (write) or input only (read)."

Read this part again:

"The default for the HLL uses record blocking if opening a file for output only (write) or input only (read)."

and then compare that with your file specification:

FFileA O A E K Disk

paying particular attention to the use of the word "ONLY" in the blocking explanation. If that's not clear enough then re-read the original paragraph (of which you quoted only part)--specifically the second sentence after the one you think should cause blocking.


Regards,
Simon Coulter.
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