The WRITETHRU option determines whether modifications to a file are written out to disk immediately or buffered internally, either by the COBOL system or by the operating system, and flushed to disk at a later stage.
WRITETHRU={ON|OFF}
ON | Write out all modifications to disk immediately. |
OFF | Flush modifications later. |
Default: | OFF |
You can obtain greater security, at the cost of significantly reduced performance, by setting this parameter to ON.