[TUHS] A few comments on porting the Bourne shell

arnold at skeeve.com arnold at skeeve.com
Sun Jan 1 20:44:37 AEST 2023


Chet Ramey <chet.ramey at case.edu> wrote:

> On 12/30/22 1:25 PM, Paul Ruizendaal wrote:
> > 
> > London and Reiser report about porting the shell that “it required by
> > far the largest conversion effort of any supposedly portable program,
> > for the simple reason that it is not portable.” By the time of SysIII
> > this is greatly improved, but also in porting the SysIII user land it
> > was the most complex of the set so far.
>
> Have you read
>
> http://www.collyer.net/who/geoff/sh.tour.pdf
>
> and looked at http://www.collyer.net/who/geoff/v7sh.tar ?
>
> In the limited literature on Bourne Shell porting, this is authoritative.
>
> Arnold Robbins built on that work and ported the v8-v10 shells to modern
> Linux versions. (I am sorry, I do not have a link right now.)

Sorry to say, it wasn't me. Geoff Collyer made the v9 sh portable
and it's available from his web site.

I did do stuff with the shell back in the 80s:

- I back-ported Ron Natalie's job control into the 4.2 BSD sh,
  along with a history mechanism I wrote from scratch that was
  inspired by csh. I posted the diffs in comp.sources.unix.

- A few very minor features were added to ksh at my suggestion.
  ISTR that one was `set -A array-name value ...' but I don't see that
  in current ksh93 doc.

- I was a reviewer for both editions of David Korn's book on ksh.

- I contributed to pdksh, although I don't remember what. The pdksh
  doc lists my name though.

- In the early 90s I did a little banging on the vi mode in the
  readline librar so that bash's vi mode would be closer to what
  I'd been used to in ksh.

In the late 80s I got interested in awk and moved almost all my
personal scripting to awk, although I still do shell work at $DAYJOB
or for personal use as needed.

Arnold


More information about the TUHS mailing list