Easiest way to use redular expressions?

[reinert <reinkor@gmail.com>]

Hello,

I made the following hack to match a string with a regular expression
(using a named pipe and grep under linux):

procedure to_os (str : String) is
   package c renames Interfaces.C;
   procedure system_rk (source : in c.char_array);
   pragma Import (c, system_rk, "system");
begin
   system_rk (Interfaces.C.To_C (str));
end to_os;

function match1(S,P : String) return boolean is
   cfile1 : constant String := "regexp_pipe0";
   file1 : File_Type;
   str1 : constant String := "echo " & S & "| grep -ic " & P;
begin
   to_os(str1 & " > regexp_pipe0 &" );
   Open(file1,In_File,cfile1);
   return b : constant boolean := Natural'Value(get_line(file1)) > 0 do
      Close(file1);
   end return;
end match1;
-----------------------------------------
OK, I assume it somehow breaks the philosophy on Ada and security/reliability.  Could someone therefore show a better and more simple way to do this? gnat.expect?

reinert