Setting widows environment variable like "path "

Question

I want to set a new value for windows environment variable path. Is there any way to set change the varibale.

Answer 1

You could also use ORA_FFI package to call Windows API function SetEnvironmentVariable. There is an example below.
See also:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dllproc/base/setenvironmentvariable.asp
kernel_lhandle Ora_Ffi.Libhandletype;
GetEnvironmentVariable_fhandle Ora_Ffi.Funchandletype;
SetEnvironmentVariable_fhandle Ora_Ffi.Funchandletype;
FUNCTION ff_GetEnvironmentVariable(
fhandle Ora_Ffi.funchandletype,
lpName varchar2,     -- address of environment variable name
lpBuffer varchar2,     -- address of buffer for variable value
nSize      pls_integer -- size of buffer, in characters
) RETURN pls_integer;
PRAGMA interface( C, ff_GetEnvironmentVariable, 11265 );
FUNCTION ff_SetEnvironmentVariable(
fhandle Ora_Ffi.funchandletype,
lpName varchar2,     -- address of environment variable name
lpValue varchar2     -- address of variable value
) RETURN pls_integer;
PRAGMA interface( C, ff_SetEnvironmentVariable, 11265 );
function SetEnvironmentVariable(lpName varchar2, lpValue varchar2) return pls_integer IS
BEGIN
return ff_SetEnvironmentVariable( SetEnvironmentVariable_fhandle, lpName, lpValue );
END;
function GetEnvironmentVariable(
lpName varchar2
) return varchar2 as
lpBuffer char(2000);     -- address of buffer for variable value
nSize      pls_integer; -- size of buffer, in characters
res pls_integer;
begin
lpBuffer:='*';
nSize:=2000-1;
res:=ff_GetEnvironmentVariable(
GetEnvironmentVariable_fhandle,
lpName,
lpBuffer,
nSize );
if res>0 then
return substr( lpBuffer, 1, res );
else
return null;
end if;
end;
-- Initialization
/* Load the library */
kernel_lhandle:=Ora_Ffi.Load_library
( '', 'kernel32.dll' );
/* GetEnvironmentVariable */
GetEnvironmentVariable_fhandle:=Ora_Ffi.Register_Function
( kernel_lhandle, 'GetEnvironmentVariableA', Ora_Ffi.C_Std );
Ora_Ffi.Register_Parameter
( GetEnvironmentVariable_fhandle, Ora_Ffi.C_CHAR_PTR );
Ora_Ffi.Register_Parameter
( GetEnvironmentVariable_fhandle, Ora_Ffi.C_CHAR_PTR );
Ora_Ffi.Register_Parameter
( GetEnvironmentVariable_fhandle, Ora_Ffi.C_INT );
Ora_Ffi.Register_Return
( GetEnvironmentVariable_fhandle, Ora_Ffi.C_INT );
/* SetEnvironmentVariable */
SetEnvironmentVariable_fhandle:=Ora_Ffi.Register_Function
( kernel_lhandle, 'SetEnvironmentVariableA', Ora_Ffi.C_Std );
Ora_Ffi.Register_Parameter
( SetEnvironmentVariable_fhandle, Ora_Ffi.C_CHAR_PTR );
Ora_Ffi.Register_Parameter
( SetEnvironmentVariable_fhandle, Ora_Ffi.C_CHAR_PTR );
Ora_Ffi.Register_Return
( SetEnvironmentVariable_fhandle, Ora_Ffi.C_INT );
To change the variable PATH you could use something like the following code:
s:=dll_path||';'||WIN32.GetEnvironmentVariable( 'PATH' );
res:=WIN32.SetEnvironmentVariable( 'PATH', s );