Re: How to exit an Ada program with (unix shell) error code?

[Adam Beneschan <adam@irvine.com>]

On May 5, 4:43 am, Martin <martin.do...@btopenworld.com> wrote:
> On May 4, 5:09 pm, a...@anon.org (anon) wrote:
>
> > --
> > --  Besides the Ada.Command_Line you can just use functions for
> > --  the instead of procedures for your nain program. This design is
> > --  great for application where Command_Line is not used.
> > --
>
> > function work return Integer is
>
> >   begin
> >     return ( 0 ) ; -- no error status code
> >   end work ;
>
> Be aware that this is not portable. The only main subprogram that all
> compilers must support (if they support a main subprogram) is "public
> parameterless library procedures" (RM2005 10.2, 29 - previous RMs have
> similar requirements), i.e.
>
>    procedure Main is
>    ...
>
> Cheers
> -- Martin


Right; and even if your Ada compiler *does* support functions that
return integers as main programs, and you're compiling for some
operating system with an "x" in its name (or Solaris), this does *not*
mean that the Ada compiler will treat the function result as the
status code.  The compiler could decide that the function result is
something to be formatted and spit out onto standard output.  If an
Ada implementation supports parameters and/or function results on main
programs, the language leaves it up to the implementation how those
are interpreted.  There's no rule that says that the interpretation
has to mimic the behavior of the C language (thank God).  So anon's
solution may work on GNAT, but it can't be assumed to work anywhere
else.

                                -- Adam