Re: bin/52458 (\n in prompt breaks history mechanism in /bin/sh)

["Ian D. Leroux" <idleroux%fastmail.fm@localhost>]

The following reply was made to PR bin/52458; it has been noted by GNATS.

From: "Ian D. Leroux" <idleroux%fastmail.fm@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: kre%NetBSD.org@localhost, netbsd-bugs%netbsd.org@localhost, gnats-admin%netbsd.org@localhost
Subject: Re: bin/52458 (\n in prompt breaks history mechanism in /bin/sh)
Date: Sat, 5 Aug 2017 08:31:25 -0400

 Thanks for the thorough explanation of the bug.
 
 On Sat,  5 Aug 2017 10:44:46 +0000 (UTC) kre%NetBSD.org@localhost wrote:
 > This can be fixed in either of two ways (I tested both, separately).
 > 
 > First, rather than testing "if PS1, new entry, else, append" change
 > it to, "If not PS2, new entry, else, append" (or if you like, "If
 > PS2, append, else new entry" which is the same thing with more code
 > churn.)
 
 Note that this, on its own, would break if I put a '\n' in PS2.  That's
 unlikely to be a problem in practice (I routinely use a newline in PS1,
 but I've never heard of anyone putting one in PS2 and it seems like a
 silly idea).
 
 > Alternatively, when the prompt is being expanded, save, and then
 > restore, the "which prompt" variable, so after the expansion is
 > done, the state is unchanged.
 
 That sounds like a more general fix.
 
 Thanks,
 
 --
 IDL