* Eric Blake wrote on Sat, Jan 22, 2011 at 02:41:39PM CET:
> On 01/22/2011 01:30 AM, Ralf Wildenhues wrote:
> > @prindex @command{unset}
> > -In some nonconforming shells (e.g., Bash 2.05a), @code{unset FOO} fails
> > -when @code{FOO} is not set. You can use
> > +In some nonconforming shells (e.g., NetBSD 5.99.43 sh or Bash 2.05a),
> > +@code{unset FOO} fails when @code{FOO} is not set. You can use
>
> Maybe add one additional sentence:
>
> This can interfere with @code{set -e} operation.
Good idea. I also added @noindent before the half-sentence after the
example.
> Looks fine with that addition.
Thanks, pushed as below,
Ralf
docs: update entry about unset.
* doc/autoconf.texi (Limitations of Builtins): NetBSD sh unset
also fails upon `unset' of a variable that is not set. Bash 2.01
could also dump core over `unset MAILPATH'.
Suggestion by Eric Blake.
diff --git a/doc/autoconf.texi b/doc/autoconf.texi
index 4cb3a8c..7eccba7 100644
--- a/doc/autoconf.texi
+++ b/doc/autoconf.texi
@@ -17758,13 +17758,15 @@ Limitations of Builtins
@item @command{unset}
@c ------------------
@prindex @command{unset}
-In some nonconforming shells (e.g., Bash 2.05a), @code{unset FOO} fails
-when @code{FOO} is not set. You can use
+In some nonconforming shells (e.g., NetBSD 5.99.43 sh or Bash 2.05a),
+@code{unset FOO} fails when @code{FOO} is not set. This can interfere
+with @code{set -e} operation. You can use
@smallexample
FOO=; unset FOO
@end smallexample
+@noindent
if you are not sure that @code{FOO} is set.
A few ancient shells lack @command{unset} entirely. For some variables
@@ -17777,8 +17779,8 @@ Limitations of Builtins
Usually, shells that do not support @command{unset} need less effort to
make the environment sane, so for example is not a problem if you cannot
unset @command{CDPATH} on those shells. However, Bash 2.01 mishandles
-@code{unset MAIL} in some cases and dumps core. So, you should do
-something like
+@code{unset MAIL} and @code{unset MAILPATH} in some cases and dumps core.
+So, you should do something like
@smallexample
( (unset MAIL) || exit 1) >/dev/null 2>&1 && unset MAIL || :
