DOS ain't dead

> > I am not sure if it could be useful for anyone, but I have just
> > reimplemented VERIFY.COM by Peter Mikalajunas -1995-
> > (https://www.ibiblio.org/pub/micro/pc-stuff/freedos/files/dos/verify/)
> in
> > pure assembler. It is not a big deal, but was a personal challenge. With
> > this main .COM executable gets reduced from 5,444 bytes to just 653
> bytes.
> >
> > Also I noticed that "original" VERIFY was not compatible with the
> internal
> > command, allowing only /ON or /OFF. My implementation works with ON and
> > OFF, but also with 1 or 0.
> >
> > Source code and binaries are available at:
> > https://sourceforge.net/projects/nikkhokkho/files/VERIFY/
>
> Thanks for sharing!
>
> I gave it a try and would like to give some feedback:
> 1. I recommended to add CRLF after ON/OFF, because that is what people
> expect. Might be not relevant for output on screen, but when redirected to
> a (log) file or for further processing.
> 2. Also (for redirected output) I recommend to always use CRLFCRLF,
> not just CRLFLF. Some text editors are other tools might be confused
> otherwise.
> 3. A source code comment reading "Show status" for a function called
> "ShowStatus" is simply a waste of space and time.
> 4. Naming a function "DoIt" is bad style. Do WHAT? "It" could mean "print
> the help screen", "exit the program", "calculate something", or whatever.
> 5. Your source code uses a mixture of tabs and spaces for indenting, e.g.,
> in ShowStatus. I recommend to enable showing whitespace and control
> characters in your text editor and clear up the mix. I came across this
> just yesterday:
> Why
> does Zig force me to use spaces instead of tabs?. Maybe it helps you
> do decide.
> 6. Trailing whitespace, e.g., in lines 52 and 63, should be removed too.
> 7. Not sure about the ".stack 64" line, because I don't use MASM-style
> assemblers, but at least on execution it's meaningless, because .COM files
> don't have a header for such information.
> 8. Also not sure about your command-line parsing. There might be
> situations, where options are preceded by whitespace (spaces, tabs, ...). I
> recommend to create a loop for skipping those.
>
> HTH, but feel free to ignore me!

Thank you for your suggestions. Being honest, all of them makes sense.

---
Visit my personal blog at https://www.javiergutierrezchamorro.com

> Q: Does your implementation verify source/destination byte-for-byte
> or simply source/destination being of equal filesize ?

It doesn't verify anything at all. It just sets/reads the verify flag for the DOS kernel.

---
Forum admin

> > I am not sure if it could be useful for anyone, but I have just
> > reimplemented VERIFY.COM by Peter Mikalajunas -1995-
> > (https://www.ibiblio.org/pub/micro/pc-stuff/freedos/files/dos/verify/)
> in
> > pure assembler. It is not a big deal, but was a personal challenge. With
> > this main .COM executable gets reduced from 5,444 bytes to just 653
> bytes.
> >
> > Also I noticed that "original" VERIFY was not compatible with the
> internal
> > command, allowing only /ON or /OFF. My implementation works with ON and
> > OFF, but also with 1 or 0.
> >
> > Source code and binaries are available at:
> > https://sourceforge.net/projects/nikkhokkho/files/VERIFY/
> >
> >
> > ------------------------------------------------------
> > Javier Gutiérrez Chamorro
> > https://www.javiergutierrezchamorro.com
>
> Q: Does your implementation verify source/destination byte-for-byte
> or simply source/destination being of equal filesize ?

It simply enables DOS verification flag. Is at the level of the driver to do the verification itself.

---
Visit my personal blog at https://www.javiergutierrezchamorro.com