gcc/ada/a-envvar.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT RUN-TIME COMPONENTS                         --
   4 --                                                                          --
   5 --              A D A . E N V I R O N M E N T _ V A R I A B L E S           --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 -- This specification is derived from the Ada Reference Manual for use with --
  10 -- GNAT.  In accordance with the copyright of that document, you can freely --
  11 -- copy and modify this specification,  provided that if you redistribute a --
  12 -- modified version,  any changes that you have made are clearly indicated. --
  13 --                                                                          --
  14 ------------------------------------------------------------------------------
  15
  16 package Ada.Environment_Variables is
  17    pragma Preelaborate (Environment_Variables);
  18
  19    function Value (Name : String) return String;
  20    --  If the external execution environment supports environment variables,
  21    --  then Value returns the value of the environment variable with the given
  22    --  name. If no environment variable with the given name exists, then
  23    --  Constraint_Error is propagated. If the execution environment does not
  24    --  support environment variables, then Program_Error is propagated.
  25
  26    function Exists (Name : String) return Boolean;
  27    --  If the external execution environment supports environment variables and
  28    --  an environment variable with the given name currently exists, then
  29    --  Exists returns True; otherwise it returns False.
  30
  31    procedure Set (Name : String; Value : String);
  32    --  If the external execution environment supports environment variables,
  33    --  then Set first clears any existing environment variable with the given
  34    --  name, and then defines a single new environment variable with the given
  35    --  name and value. Otherwise Program_Error is propagated.
  36    --  If implementation-defined circumstances prohibit the definition of an
  37    --  environment variable with the given name and value, then
  38    --  Constraint_Error is propagated.
  39    --  It is implementation defined whether there exist values for which the
  40    --  call Set(Name, Value) has the same effect as Clear (Name).
  41
  42    procedure Clear (Name : String);
  43    --  If the external execution environment supports environment variables,
  44    --  then Clear deletes all existing environment variables with the given
  45    --  name. Otherwise Program_Error is propagated.
  46
  47    procedure Clear;
  48    --  If the external execution environment supports environment variables,
  49    --  then Clear deletes all existing environment variables. Otherwise
  50    --  Program_Error is propagated.
  51
  52    procedure Iterate
  53      (Process : not null access procedure (Name, Value : String));
  54    --  If the external execution environment supports environment variables,
  55    --  then Iterate calls the subprogram designated by Process for each
  56    --  existing environment variable, passing the name and value of that
  57    --  environment variable. Otherwise Program_Error is propagated.
  58
  59 end Ada.Environment_Variables;