Re: possible code error at run_command.c

[Frank Li <lznuaa@gmail.com>]

>
> Disable this check - it just takes away performance. :-)

Release version will disable this.
Debug version enable this by default is just for find out code error.

>
> (If you don't disable the check, then keep the required changes private.)
>
>> I prefer change it to
>> int failed_errno = errno;
>
> You don't need to initialize the variable at all because it is always
> initialized elsewhere before it is used. Perhaps MSVC is clever enough to
> see it?
>

Maybe some excute path miss initialized it. Otherwise compiler will
not report warning.