What does RECFM=FS mean? How does it differ from RECFM=F? Sent from my iPhone
> On Jan 5, 2017, at 20:12, Bill Woodger <[email protected]> wrote: > > Yet in modern times the S for F has its uses. If a C/C++ program is going to > use a "seek" for a file, if the file is F/FB, then the file will be read from > the start to satisfy the seek (because there may be those embedded short > blocks), but if the file is FS/FBS (guarantee, by the person who put the S in > the RECFM, to not have embedded short blocks) then the seek is able to > calculate the position of he block containing the sought record, and then > only have to read within the block. > > I'm sure all C/C++ programmers who want to use seek on z/OS know that, since > it is documented. Yeah. Right. (at risk of starting war) people who want to > code seek to save a bit of thinking are exactly the ones who read the manuals. > > What this means is "if you are using seek in a C/C++ program to access > fixed-length records, ensure RECFM=FS/FBS. If you haven't done that, do it, > and compare the resource usage. > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
