But the commands in the subshell execute inside a different shell execution context so they shouldn't have their own set -e context (Section 2.12)?
I don't see where the spec says that the subshell has to inherit the and/or list-ness of the parent context. Section 2.12 doesn't mention that as being one of the things that a subshell inherits (and unless I'm missing a good use-case, it seems like a pretty useless thing to inherit in a subshell or a function that happens to be called on the LHS of an and/or). On Wed, Nov 13, 2019 at 3:07 PM Chet Ramey <chet.ra...@case.edu> wrote: > > On 11/13/19 5:24 AM, Shaun Crampton wrote: > > > Bash Version: 5.0 > > Patch Level: 3 > > Release Status: release > > > > Description: > > I was trying to get a function to return early if a command > > fails by putting > > the body of the function in a subshell and using set -e inside > > the subshell. > > If I run a subshell on its own, this works, but when I try to > > combine it > > into a larger program, the set -e gets ignored. > > > > Repeat-By: > > Managed to boil it down to this smaller example: > > > > # On its own, subshell behaves as expected: > > $ ( set -ex; false; echo here ) > > + false > > > > # In a list, behaviour changes, "echo here" gets executed: > > $ ( set -ex; false; echo here ) && echo there > > + false > > + echo here > > here > > there > > The subshell command is part of an and-or list, so the -e is ignored for > that command: > > "The -e setting shall be ignored when executing the compound list following > the while, until, if, or elif reserved word, a pipeline beginning with the > ! reserved word, or any command of an AND-OR list other than the last." > > (from > https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_25_03) > > The subshell inherits this state (being part of an and-or list) from its > parent. > > > > > # If the subshell is executed in the background, it works > > $ ( set -e; false; echo here ) & pid=$!; wait $pid && echo there > > In this command, the subshell is not part of an and-or list. > > -- > ``The lyf so short, the craft so long to lerne.'' - Chaucer > ``Ars longa, vita brevis'' - Hippocrates > Chet Ramey, UTech, CWRU c...@case.edu http://tiswww.cwru.edu/~chet/
