Re: another option that deserves a mention on .ONESHELL doc page is -x

[David Boyce]

I won't address the main point, but if you add -x to .SHELLFLAGS you ought
to add .SILENT: as well to solve the problem of "repeating the commands a
second time":

$ cat Makefile
.ONESHELL:
.SILENT:

test: .SHELLFLAGS = -e -x -c
test:
        true
        ls nonexistent
        touch $@

$ make
+ true
+ ls nonexistent
ls: cannot access nonexistent: No such file or directory
make: *** [Makefile:6: test] Error 2

On Sat, Jan 8, 2022 at 3:11 PM Britton Kerin <britton.kerin@gmail.com>
wrote:

> I don't know how POSIX-ish it is but IMO -x deserves a mention,
> especially since -e gets one.  It's a little annoying that it end up
> repeating the commands a second time, but without it you end up with
> all the commands listed, followed by an error for one of the early
> ones which is confusing at best and ambiguous about where the error
> actually occurred at worst.
>
> With -x:
>
>      $ cat Makefile
>      .ONESHELL:
>
>      test: .SHELLFLAGS = -e -x -c
>      test:
>              true
>              ls nonexistent
>              touch $@
>      $ make test
>      true
>      ls nonexistent
>      touch test
>      + true
>      + ls nonexistent
>      ls: cannot access 'nonexistent': No such file or directory
>      make: *** [Makefile:5: test] Error 2
>
> Without -x:
>
>      $ cat Makefile
>      .ONESHELL:
>
>      test: .SHELLFLAGS = -e -c
>      test:
>              true
>              ls nonexistent
>              touch $@
>      $ make test
>      true
>      ls nonexistent
>      touch test
>      ls: cannot access 'nonexistent': No such file or directory
>      make: *** [Makefile:5: test] Error 2
>
>