From mboxrd@z Thu Jan  1 00:00:00 1970
From: "G.raud" <graud@gmx.com>
Subject: [BUG] ignored substring parameter expansion after $@ ("$@""${v%/*}")
 command line)
Date: Tue, 26 Sep 2017 05:39:59 +0200
Message-ID: <20170926033942.z4m5jglztiqjxzda@gmx.com>
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To test that the param susbtitution in "$@""${v%*/}" is ignored (on a
command line or in an assignment):

$ dash -c 'v=1/2; w="$@""${v#*/}"; echo "$@""${v#*/}" "$w"'

Note that the quoting has to be around each variable, that the first has
to be $@ and that the bug occurs with %, %%, #, or ## substring
processing.

Adding a string in between the 2 required vars does not change the
behaviour:

$ dash -c 'v=1/2; echo "$@"s$u"s${v#*/}"'

except by adding a string, even empty, inside the quoting of $@:

$ dash -c 'v=1/2; echo "$a$@""${v#*/}"'

Regards

-- 
G.raud Meyer
graud@gmx.com