chdrive.c

ReactOS是一些高手根据Windows XP的内核编写出的类XP。内核实现机理和API函数调用几乎相同。甚至可以兼容XP的程序。喜欢研究系统内核的人可以看一看。

/*
 * COPYRIGHT:   See COPYING in the top level directory
 * PROJECT:     ReactOS system libraries
 * FILE:        lib/crt/??????
 * PURPOSE:     Unknown
 * PROGRAMER:   Unknown
 * UPDATE HISTORY:
 *              25/11/05: Added license header
 */

#include <precomp.h>

/*
 * @implemented
 *
 *    _chdrive (MSVCRT.@)
 *
 * Change the current drive.
 *
 * PARAMS
 *  newdrive [I] Drive number to change to (1 = 'A', 2 = 'B', ...)
 *
 * RETURNS
 *  Success: 0. The current drive is set to newdrive.
 *  Failure: -1. errno indicates the error.
 *
 * NOTES
 *  See SetCurrentDirectoryA.
 */
int _chdrive(int newdrive)
{
  WCHAR buffer[] = L"A:";

  buffer[0] += newdrive - 1;
  if (!SetCurrentDirectoryW( buffer ))
  {
    _dosmaperr(GetLastError());
    if (newdrive <= 0)
    {
      __set_errno(EACCES);
    }
    return -1;
  }
  return 0;
}