1 ------------------------------------------------------------------------------
3 -- GNAT RUN-TIME COMPONENTS --
5 -- A D A . C O M M A N D _ L I N E --
11 -- Copyright (C) 1992-2002 Free Software Foundation, Inc. --
13 -- This specification is derived from the Ada Reference Manual for use with --
14 -- GNAT. The copyright notice above, and the license provisions that follow --
15 -- apply solely to the contents of the part following the private keyword. --
17 -- GNAT is free software; you can redistribute it and/or modify it under --
18 -- terms of the GNU General Public License as published by the Free Soft- --
19 -- ware Foundation; either version 2, or (at your option) any later ver- --
20 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
21 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
22 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
23 -- for more details. You should have received a copy of the GNU General --
24 -- Public License distributed with GNAT; see file COPYING. If not, write --
25 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
26 -- MA 02111-1307, USA. --
28 -- As a special exception, if other files instantiate generics from this --
29 -- unit, or you link this unit with other files to produce an executable, --
30 -- this unit does not by itself cause the resulting executable to be --
31 -- covered by the GNU General Public License. This exception does not --
32 -- however invalidate any other reasons why the executable file might be --
33 -- covered by the GNU Public License. --
35 -- GNAT was originally developed by the GNAT team at New York University. --
36 -- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). --
38 ------------------------------------------------------------------------------
40 package Ada.Command_Line is
41 pragma Preelaborate (Command_Line);
43 function Argument_Count return Natural;
44 -- If the external execution environment supports passing arguments to a
45 -- program, then Argument_Count returns the number of arguments passed to
46 -- the program invoking the function. Otherwise it return 0.
48 -- In GNAT: Corresponds to (argc - 1) in C.
50 function Argument (Number : Positive) return String;
51 -- If the external execution environment supports passing arguments to
52 -- a program, then Argument returns an implementation-defined value
53 -- corresponding to the argument at relative position Number. If Number
54 -- is outside the range 1 .. Argument_Count, then Constraint_Error is
57 -- in GNAT: Corresponds to argv [n] (for n > 0) in C.
59 function Command_Name return String;
60 -- If the external execution environment supports passing arguments to
61 -- a program, then Command_Name returns an implementation-defined value
62 -- corresponding to the name of the command invoking the program.
63 -- Otherwise Command_Name returns the null string.
65 -- in GNAT: Corresponds to argv [0] in C.
67 type Exit_Status is new Integer;
69 Success : constant Exit_Status;
70 Failure : constant Exit_Status;
72 procedure Set_Exit_Status (Code : Exit_Status);
74 ------------------------------------
75 -- Note on Interface Requirements --
76 ------------------------------------
78 -- If the main program is in Ada, this package works as specified without
79 -- any other work than the normal steps of WITH'ing the package and then
80 -- calling the desired routines.
82 -- If the main program is not in Ada, then the information must be made
83 -- available for this package to work correctly. In particular, it is
84 -- required that the global variable "gnat_argc" contain the number of
85 -- arguments, and that the global variable "gnat_argv" points to an
86 -- array of null-terminated strings, the first entry being the command
87 -- name, and the remaining entries being the command arguments.
89 -- These correspond to the normal argc/argv variables passed to a C
90 -- main program, and the following is an example of a complete C main
91 -- program that stores the required information:
93 -- main(int argc, char **argv, char **envp)
95 -- extern int gnat_argc;
96 -- extern char **gnat_argv;
97 -- extern char **gnat_envp;
107 -- The assignment statements ensure that the necessary information is
108 -- available for finding the command name and command line arguments.
111 Success : constant Exit_Status := 0;
112 Failure : constant Exit_Status := 1;
114 -- The following locations support the operation of the package
115 -- Ada.Command_Line.Remove, whih provides facilities for logically
116 -- removing arguments from the command line. If one of the remove
117 -- procedures is called in this unit, then Remove_Args/Remove_Count
118 -- are set to indicate which arguments are removed. If no such calls
119 -- have been made, then Remove_Args is null.
121 Remove_Count : Natural;
122 -- Number of arguments reflecting removals. Not defined unless
123 -- Remove_Args is non-null.
125 type Arg_Nums is array (Positive range <>) of Positive;
126 type Arg_Nums_Ptr is access Arg_Nums;
127 -- An array that maps logical argument numbers (reflecting removal)
128 -- to physical argument numbers (e.g. if the first argument has been
129 -- removed, but not the second, then Arg_Nums (1) will be set to 2.
131 Remove_Args : Arg_Nums_Ptr := null;
132 -- Left set to null if no remove calls have been made, otherwise set
133 -- to point to an appropriate mapping array. Only the first Remove_Count
134 -- elements are relevant.
136 pragma Import (C, Set_Exit_Status, "__gnat_set_exit_status");
138 end Ada.Command_Line;