Re: Windows LDAP group-user checking in Ada 95

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Thu, 16 Feb 2012 12:38:54 -0800 (PST), Rego, P. wrote:

> For getting the username, I have the function (in Ada 95):
> 
> function GetUsername return String is
>    function GetEnv (Variable : String) return Interfaces.C.Strings.chars_ptr;
>    pragma Import (C, GetEnv, "getenv");
> 
>    Command : constant String := "USERNAME";
>    Answer_Ptr : constant Interfaces.C.Strings.chars_ptr := GetEnv (Command);
>    Answer : constant String := Interfaces.C.Strings.Value (Answer_Ptr);
> begin
>    return Answer;
> end GetUsername;

This is wrong, you cannot pass String to a C program. Then the user name
variable is named USER.

with Interfaces.C.Strings;
use  Interfaces.C;
use  Interfaces.C.Strings;

function GetUsername return String is -- Constraint_Error when undefined
   function GetEnv (Variable : char_array) return chars_ptr;
   pragma Import (C, GetEnv, "getenv");
begin
   return Value (GetEnv (To_C ("USER")));
end GetUsername;

But you don't need that because there already exist the package
Ada.Environment_Variables.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de