Tue, 20 Apr 1999 09:39:26 -0500
|
> On second thought, this version is better. The previous version doesn't
> give you any way of differentiating between an undefined env var, and a
> defined env var that happens to have a zero-length string as its value.
>
> function getenv (Name : String)
> return Interfaces.C.Strings.Chars_Ptr is ...
> Matthew Heaney's solution works if the environment variable exists,
> but raises an exception if it does not. I offer this refinement of
> Matthew's solution, where the exception is raised, but with
> information supplied which quickly pinpoints the cause of the
> exception.
I disagree with both of you. I think the best solution is to start with
the GNAT package Ada.Command_Line.Environment, and if necessary, modify it
to do what you want. It is covered by the "special exception" to the
GPL. Why start over on a problem that has been solved?
The following program has output identical to ksh printenv :
with Ada.Command_Line.Environment;
with Ada.Text_IO;
procedure CL_Test is
begin
for I in 1 .. Ada.Command_Line.Environment.Environment_Count loop
Ada.Text_IO.Put_Line (Ada.Command_Line.Environment.Environment_Value (I));
end loop;
end CL_Test;
|
|
|