Re: Q: bash: trap in subshell

[Chet Ramey]

Dmitry V. Levin wrote:
> Hi,
>
> I wonder whether such difference in "trap" behavior is valid:
>
> $ sh -c 'f() { echo f; }; t() { trap f EXIT; trap; }; t'
> trap -- 'f' EXIT
> f
> $ sh -c 'f() { echo f; }; t() { trap f EXIT; trap; }; t&'
> trap -- 'f' EXIT
> $ sh -c 'f() { echo f; }; t() { trap f EXIT; trap; }; (t)&'
> trap -- 'f' EXIT
> f

Bash does not run the exit trap in a process forked to run an
asynchronous simple command, regardless of whether or not that
command is a shell function or builtin.  It makes special provisions
to run the exit trap in a user-specified subshell -- () -- even
when that subshell is run asynchronously.

Chet
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
                       Live Strong.  No day but today.
Chet Ramey, ITS, CWRU    chet@case.edu    http://cnswww.cns.cwru.edu/~chet/