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To: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
Cc: tr AT eth DOT net, djgpp-workers AT delorie DOT com
Cc: autoconf AT gnu DOT org
Subject: portability of sed's \{0,1\}?
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From: Jim Meyering <meyering AT ascend DOT com>
In-Reply-To: "Eli Zaretskii"'s message of "Fri, 11 Aug 2000 20:39:18 +0200"
Date: 11 Aug 2000 20:11:25 +0200
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Reply-To: djgpp-workers AT delorie DOT com

"Eli Zaretskii" <eliz AT is DOT elta DOT co DOT il> writes:
| > | Also, is \{0,1\} supported in all versions of
| > |      Sed?
| >
| > I'm almost positive that it's not portable.
|
| Then what is the portable repacement for the ? operator (which isn't
| part of the basic regexps, and therefore isn't supported by Sed)?

I'm not so sure now.
I've tested on a pretty wide range of systems
(did this: for i in $(type -a -p sed); do echo bc |$i 's/a\{0,1\}bc/x/';done)
and it worked fine (printed `x') for each version of sed on each of those
systems.

I tested on a few flavors of Suns (sunos4.1.4, 5.5.1, 5.6, 5.7),
HPUX 10.20, Linux, irix 6.2 & 6.5, NetBSD 1.3.1, AIX 2.4.

I saw the earlier thread (on the autoconf list) on this topic where
someone found that `?' and \| were not portable.  Has anyone found a
system on which \{m,n\} is not portable?