Hi,
pdksh and mksh R52 (the latest release), but not some intermediate
versions, do this, note POSIX mode:
tg@blau:~ $ cat x
ACRO_INSTALL_DIR=/usr/Acroread/Reader
directory="`basename \"$ACRO_INSTALL_DIR\"`"
echo "<$directory>"
tg@blau:~ $ mksh -o posix x
<Reader">
tg@blau:~ $ mksh x
<Reader>
None of the other shells I tested so far has this (not even
bash --posix), but the behaviour is consistent with the comments
found in pdksh source code which I reformatted and resynchronised
with the current section numbers:
/*
* We need to know whether we are within double
* quotes, since most shells translate \" to "
* within "…`…\"…`…". This is not done in POSIX
* mode (§2.2.3 Double-Quotes: “The backquote
* shall retain its special meaning introducing
* the other form of command substitution (see
* Command Substitution). The portion of the
* quoted string from the initial backquote and
* the characters up to the next backquote that
* is not preceded by a <backslash>, having
* escape characters removed, defines that
* command whose output replaces "`...`" when
* the word is expanded.”; §2.6.3 Command
* Substitution: “Within the backquoted style
* of command substitution, <backslash> shall
* retain its literal meaning, except when
* followed by: '$', '`', or <backslash>. The
* search for the matching backquote shall be
* satisfied by the first unquoted non-escaped
* backquote; during this search, if a
* non-escaped backquote is encountered[…],
* undefined results occur.”).
*/
I only noticed this being a problem now because some legacy
script (with /bin/sh shebang, which invokes POSIX mode on
some systems with mksh) breaks due to it.
Question:
Am I interpreting the current standard correctly, and is
<Reader"> indeed the only correct output? If yes, will this
also be true for a future version of the standard (as far
as this can be said currently, i.e. are there any plans to
change it)? If no, is <Reader> a/the correct output?
Thanks in advance,
//mirabilos, who really really really dislikes U+0060
--
(gnutls can also be used, but if you are compiling lynx for your own use,
there is no reason to consider using that package)
-- Thomas E. Dickey on the Lynx mailing list, about OpenSSL
