Re: "trap" output from "if" statement redirected wrongly

[Chet Ramey]

On 4/13/22 8:58 AM, Frank Heckenbach wrote:

> Bash Version: 5.1
> Patch Level: 16
> Release Status: release
>
> Description:
>
> This script writes "foo" to bar rather than stdout as I'd expect.

That's not unreasonable, but it's not how it works.

> It's triggered by the "if" statement (which doesn't even cause
> running in a subshell, so it's not that).

The entire `if' statement executes with its stdout redirected. That means
the `false' that causes the shell to exit immediately has its stdout
redirected, which the exit trap inherits.

Most shells behave like bash does here; dash is a notable exception.


--
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU    chet@case.edu    http://tiswww.cwru.edu/~chet/