On Fri, 4 Jun 2021 at 14:12, Radoslaw Skorupka <[email protected]> wrote: > W dniu 04.06.2021 o 19:48, Paul Gilmartin pisze:
> > Block boundaries? Sometimes they matter, and RDWs and BDWs. Especially > > for RCFM=vBS > > such as IEBCOPY PDSU. And LRECL=X. > > > > AWSTAPE? > > Your brevity is excellent, but it doesn't explain what and how to do. The fundamental problem is that a tape - whether 3420-type (9-track, several possible BPIs and recording techniques), or more modern 3480, 3490, etc. - cannot be represented by a byte stream. It's not a simple matter of binary vs character or the like; there is out-of-band data - tape marks, block lengths, EOFs, and maybe a couple more. So AWS is a solution (one of several) that represents a tape as a byte stream. The original AWS format is very simple and well documented by IBM, though there are a few incompatible extensions made by at least IBM, Funsoft, and the Hercules developers. It is trivial to write a program (REXX, C, COBOL?, whatever) to read an AWS file and convert it into something useful, for example a sequential file for each tape file. This can run on any platform, and of course the target file format will to some extent be platform specific. > I just checked CBTtape - there are MVS (z/OS) tools - unapplicable for PC. > There is also Windows tool - AWS browser. Also unapplicable. Why unapplicable? > There is another requirement here: to read REAL tape using PC tools. > How to read? > a) dataset by dataset > b) whole tape => AWS tape image The usual approach that I've used many times is to use the Hercules tapecopy program, which runs on any system that can host Hercules, i.e. pretty much any UNIX-like system, or Windows. It reads a physical tape (assuming some minimal driver support for the host OS), and writes an AWS file. Then you write a program to process that file, or you use one of several standard tools (awsbrowse - there are a couple of different programs with this name, but you dismiss it for some reason) to copy the data you want and convert it into something you can make use of. > I believe there are tools to read tape and understand blocks and > tapemarks, and maybe SL labels. > Less chance for AWS utility, especially there is such tool working under z/OS. I don't understand what this last bit means. AWS format is so simple that anyone can easily write a program to handle it. But finally, the OP's requirement is unclear to me. He speaks of archiving some tapes, so presumably there is a wish to not keep the physical tapes which use 1960s/70s densities, are likely to continue to deteriorate in storage, and anyway could probably all fit on a little USB stick. No problem to use AWS format and then put the USB stick in the vault. Or the cloud, or whatever. But what is needed when it comes time to retrieve the archive and do <something> with the data? PC tools? Restore to z/OS 5.9 or something in 2042? All is possible - there are z/OS tools to read an AWS file and write to a real tape drive. Or of course Hercules tapecopy can do the same thing on a PC. Tony H. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
