使用流

本主题中的示例演示如何使用基本的 NTFS 文件系统流。

此示例创建一个名为“TestFile”的文件,其大小为 16 个字节。 但是,该文件还有一个额外的 ::$DATA 流类型,名为“Stream”,它添加了操作系统未报告的额外 23 个字节。 因此,查看文件的文件大小属性时,只能看到该文件的默认 ::$DATA 流的大小。

#include <windows.h>
#include <stdio.h>

void main( )
 {
  HANDLE hFile, hStream;
  DWORD dwRet;

  hFile = CreateFile( TEXT("TestFile"), // Filename
                      GENERIC_WRITE,    // Desired access
                      FILE_SHARE_WRITE, // Share flags
                      NULL,             // Security Attributes
                      OPEN_ALWAYS,      // Creation Disposition
                      0,                // Flags and Attributes
                      NULL );           // OVERLAPPED pointer
  if( hFile == INVALID_HANDLE_VALUE )
   {
    printf( "Cannot open TestFile\n" );
    return;
   }
  else
   {
    WriteFile( hFile,              // Handle
               "This is TestFile", // Data to be written
               16,                 // Size of data, in bytes
               &dwRet,             // Number of bytes written
               NULL );             // OVERLAPPED pointer
    CloseHandle( hFile );
    hFile = INVALID_HANDLE_VALUE;
   }

  hStream = CreateFile( TEXT("TestFile:Stream"), // Filename
                        GENERIC_WRITE,           // Desired access
                        FILE_SHARE_WRITE,        // Share flags
                        NULL,                    // Security Attributes
                        OPEN_ALWAYS,             // Creation Disposition
                        0,                       // Flags and Attributes
                        NULL );                  // OVERLAPPED pointer
  if( hStream == INVALID_HANDLE_VALUE )
    printf( "Cannot open TestFile:Stream\n" );
  else
   {
    WriteFile( hStream,                   // Handle
               "This is TestFile:Stream", // Data to be written
               23,                        // Size of data
               &dwRet,                    // Number of bytes written
               NULL);                     // OVERLAPPED pointer
    CloseHandle( hStream );
    hStream = INVALID_HANDLE_VALUE;
   }
}

如果在命令提示符下键入 Type TestFile ,则会显示以下输出:

This is TestFile

但是,如果键入单词 Type TestFile:Stream,则会生成以下错误:

“文件名、目录名称或卷标签语法不正确。”

若要查看 TestFile:stream 中的内容,请使用以下命令之一:

更多 < TestFile:Stream

更多 < TestFile:Stream:$DATA

显示的文本如下所示:

This is TestFile:Stream

文件流