On Mon, Apr 03, 2023 at 10:30:29AM -0400, Chet Ramey wrote:
> On 3/31/23 10:20 PM, Zev Weiss wrote:
>
> > Bash Version: 5.2
> > Patch Level: !PATCHLEVEL!
> > Release Status: release
> >
> > Description:
> >
> > When 'set -e' is enabled, file-content substitutions of the form $(<...)
> > cause an immediate exit even when the subsitution is in a conditional
> > context such as the condition of an 'if' statement or the left operand
> > of the '||' operator.
>
> It's always been a (fatal) redirection error, but, as you suspect, has a
> different effect now that $(<file) is run without forking. I'll change it
> to a non-fatal failed word expansion for this case.
Very interesting.
I agree that it makes more sense as a non-fatal shell error.
I am a bit surprised that the problem only occurs when errexit is on,
and not when it is off though.
In any case, a possible workaround, for now, is to use the usual
technique to "catch" fatal errors:
# in standard mode
if ! eval 'x=$(</nosuchfile)'; then
x=''
echo hello
fi
Or:
# in POSIX mode or standard mode
if ! command eval 'x=$(</nosuchfile)'; then
x=''
echo hello
fi
emanuele6
