From: Andrej Borsenkow <borsenkow.msk@sni.de>
To: Zoltan Hidvegi <hzoli@cs.elte.hu>
Cc: zsh-workers@math.gatech.edu
Subject: Re: Order of field splitting in zsh
Date: Wed, 22 Jan 1997 18:58:34 +0300 (MSK) [thread overview]
Message-ID: <Pine.SV4.3.95.970122183037.1005A-100000@itsrm1.mow.sni.de> (raw)
In-Reply-To: <199701161555.QAA10160@bolyai.cs.elte.hu>
On Thu, 16 Jan 1997, Zoltan Hidvegi wrote:
> Andrej Borsenkow wrote:
> >
> > POSIX.2 defines the following order of expansions in sh:
> >
> > 1. tilde expansion, parameter expansion, command substitution, arithmetic
> > expansion
> > 2. field splitting (_after_ the above)
> > 3. pathname expansion (globbing)
> > 4. qoute removal.
> >
> > It seems, that zsh (even if invoked as sh) does field splitting on result
> > of command substitution _immidiately_ after getting the value. The
> > example is:
> >
...
>
> You are right but that can only cause problems when IFS changes in step
> one, and under POSIX it can only happen when it was set to the empty string
> previously. I checked AT&T ksh and pdksh:
>
...
>
> As you see ksh behaves like zsh. Bash behaves as POSIX requires. But I do
> not think it is a real problem, and the fix would just complicate the code
> unnecessarily. Note that both ksh I tested claims POSIX compilance.
>
There is more simple case:
% ./sh (where sh -> /bin/zsh)
% args $(echo 'a ')$(echo 'b')
^ note blank here (or any IFS white space)
1
ab
% /bin/ksh
% args $(echo 'a ')$(echo 'b')
2
a
b
%
The same with /bin/sh (well, my /bin/sh doesn't understand $(...) but with
`...` it behaves like ksh).
greetings
-------------------------------------------------------------------------
Andrej Borsenkow Fax: +7 (095) 252 01 05
SNI ITS Moscow Tel: +7 (095) 252 13 88
NERV: borsenkow.msk E-Mail: borsenkow.msk@sni.de
-------------------------------------------------------------------------
next prev parent reply other threads:[~1997-01-22 16:20 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
1997-01-16 14:07 Andrej Borsenkow
1997-01-16 15:55 ` Zoltan Hidvegi
1997-01-22 15:58 ` Andrej Borsenkow [this message]
1997-01-22 21:59 ` Zoltan Hidvegi
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=Pine.SV4.3.95.970122183037.1005A-100000@itsrm1.mow.sni.de \
--to=borsenkow.msk@sni.de \
--cc=hzoli@cs.elte.hu \
--cc=zsh-workers@math.gatech.edu \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public inbox
https://git.vuxu.org/mirror/zsh/
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).