Re: [PATCH v3] posix: Fix system blocks SIGCHLD erroneously [BZ #30163]

[Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>]

On 03/03/23 02:11, Adam Yi wrote:
> Thanks for reviewing!

> 
>     Add some parsing check here:
> 
>        TEST_VERIFY_EXIT  (argv[0] != NULL);
>        char *endptr = NULL;
>        double sec = strtod (argv[0], &endptr);
>        TEST_VERIFY_EXIT (endptr != argv[0] && errno != ERANGE);
>        /* No suffix support and only positive values.  */
>        TEST_VERIFY_EXIT (sec >= 0.0);
> 
> 
> I'm not sure if TEST_VERIFY_EXIT is the correct thing to do here, since it's the mocked /bin/sh,
> not directly part of the test. It's weird that providing invalid argument to `sleep` would crash the shell.
> Would it make more sense to print an error to stderr and return 1? FWIW, I didn't add parsing check
> here because I saw that other functions here do not have any sanity checks. exit and kill are just
> calling atoi without checking for errors and they don't check return values either. There are some
> checks in copy_func but it doesn't even check that there are two arguments before referencing them.

Printing an error to stderr is fine, and indeed it follow better
the mock shell way. 

I want to add some sanity check to avoid issuing invalid argument to sleep 
that returns immediately or setup an unexpected timer, which might be tricky 
to debug (specially in the container environment).  Failing early with a message 
catch possible tests issues.