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

[anon@anon.org (anon)]

Actually, Adam the design for all OS currectly use today states that if the 
program returns the "Accumulator Register" will contain the program exit 
code. Been a standard for at least 40 years.


In <62b174a9-c9c5-479c-9dd6-71916c102eb0@z16g2000prd.googlegroups.com>, Adam Beneschan <adam@irvine.com> writes:
>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