Bug#811092: unportability of "…`…\"…\"…`…"

[Thorsten Glaser <tg@mirbsd.de>]

Hi all,

I’ve had mksh R52b released uploaded which alleviates this problem
somewhat: it deliberately adds back a bug that violates POSIX even
in “set -o posix” mode, because we think POSIX is broken here.

I’ll keep that in until the Austin Group decides on this issue,
either way. Depending on what they decide, however, your use of
"…`…\"…\"…`…" in shell (fixed in texlive-bin already) may still
be broken, and, in any case, it’s unportable so dbconfig-common
should still switch to $(…) style command substitution.

Clarification: I’m asking POSIX to either allow (or recommend)
or even require that…

	$ set -o posix
	$ echo "`echo \"foo\"`"

… echos “foo”, whereas (in mksh R52 and yash) it echos “"foo"”,
which a strict reading of the current standard requires. (Or to
tell me my (and the yash developers’) reading of the standard is
incorrect, but I don’t think so.)

JFYI,
//mirabilos
-- 
“It is inappropriate to require that a time represented as
 seconds since the Epoch precisely represent the number of
 seconds between the referenced time and the Epoch.”
	-- IEEE Std 1003.1b-1993 (POSIX) Section B.2.2.2