workbench/c/shellcommands/Unsetenv.c

   1 /*
   2     Copyright © 1995-2010, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: UnSetEnv CLI command
   6     Lang: English
   7 */
   8
   9 /*****************************************************************************
  10
  11     NAME
  12
  13         UnSetEnv
  14
  15     SYNOPSIS
  16
  17         NAME,SAVE/S
  18
  19     LOCATION
  20
  21         C:
  22
  23     FUNCTION
  24
  25         Unsets a global variable from the current shell. These variables can
  26         be accessed from any program executing at any time.
  27
  28         These variables are usually not saved in the ENVARC: directory, hence they
  29         can only be used by programs during the current execution of the
  30         operating system. If set using SAVE argument, the variable is also saved
  31         in ENVARC: and can then be deleted there by UnSetEnv with the SAVE argument.
  32
  33         If no parameter is specified, the current list of global variables
  34         is displayed.
  35
  36     INPUTS
  37
  38         NAME    - The name of the global variable to unset.
  39
  40         SAVE    - Unset (delete) the variable also in ENVARC:
  41
  42     RESULT
  43
  44         Standard DOS error codes.
  45
  46     NOTES
  47
  48     EXAMPLE
  49
  50         UnSetEnv EDITOR SAVE
  51
  52             Any program that accesses the variable "EDITOR" (like More and
  53             MultiView) are able to find out the name of the text-editor the
  54             user would like to use, by examining the contents of the variable.
  55             This command would delete this variable in Ram (in ENV:) _and_ in
  56             ENVARC: (assuming it was already set there, for example by the use
  57             of the SAVE argument of SetEnv).
  58
  59     BUGS
  60
  61     SEE ALSO
  62
  63         GetEnv, SetEnv
  64
  65     INTERNALS
  66
  67     HISTORY
  68
  69 ******************************************************************************/
  70
  71 #include <proto/dos.h>
  72 #include <proto/exec.h>
  73
  74 #include <dos/dos.h>
  75 #include <dos/exall.h>
  76 #include <dos/rdargs.h>
  77 #include <dos/var.h>
  78 #include <exec/memory.h>
  79 #include <exec/types.h>
  80 #include <utility/tagitem.h>
  81 #include <aros/shcommands.h>
  82
  83 AROS_SH2(UnSetEnv, 45.0,
  84 AROS_SHA(STRPTR, , NAME,   , NULL),
  85 AROS_SHA(IPTR  , , SAVE, /S, NULL))
  86 {
  87     AROS_SHCOMMAND_INIT
  88
  89     int     Return_Value;
  90     BOOL    Success;
  91     BPTR    lock;
  92     TEXT    progname[108];
  93
  94     GetProgramName(progname, sizeof(progname));
  95     Return_Value = RETURN_OK;
  96
  97     if (SHArg(NAME) != NULL)
  98     {
  99         /* Delete the global variable from the list.
 100          */
 101         Success = DeleteVar(SHArg(NAME),
 102                             SHArg(SAVE) ? GVF_GLOBAL_ONLY | GVF_SAVE_VAR : GVF_GLOBAL_ONLY);
 103
 104         if (Success == FALSE)
 105         {
 106             UBYTE buf[FAULT_MAX+128];
 107
 108             Fault(-141, NULL, buf, sizeof(buf));
 109             Printf(buf, SHArg(NAME));
 110             PrintFault(IoErr(), progname);
 111
 112             Return_Value = RETURN_ERROR;
 113         }
 114     }
 115     else
 116     {
 117         /* Display a list of global variables.
 118          */
 119
 120         lock = Lock("ENV:", ACCESS_READ);
 121         if (lock)
 122         {
 123             struct FileInfoBlock *FIB = AllocDosObject(DOS_FIB, NULL);
 124
 125             if (FIB)
 126             {
 127                 if(Examine(lock, FIB))
 128                 {
 129                     while(ExNext(lock, FIB))
 130                     {
 131                         /* don't show dirs */
 132                         if (FIB->fib_DirEntryType < 0)
 133                         {
 134                             PutStr(FIB->fib_FileName);
 135                             PutStr("\n");
 136                         }
 137                     }
 138                 }
 139                 FreeDosObject(DOS_FIB, FIB);
 140             }
 141             UnLock(lock);
 142         }
 143         else
 144         {
 145             PrintFault(IoErr(), progname);
 146
 147             Return_Value = RETURN_FAIL;
 148         }
 149     }
 150
 151     return Return_Value;
 152
 153     AROS_SHCOMMAND_EXIT
 154 } /* main */