x64 programming #1: 環境變數及特殊目錄..

2008/07/25 .NET 技術隨筆

被 X64 折騰了這麼久,總要留些戰蹟下來... 先從每個人都會碰到的目錄路徑調整開始吧...

有些目錄大家都耳熟能詳,像是 c:\Program Files\ 之類的,不過如果你的程式把這種路徑寫死了,你就要注意了... 因為到了 x64 位元下的 x86 相容模式,路徑就完全不一樣了... 先來看這一段程式執行結果是啥? 別急著看解答,猜一下..

印出所有 SpecialFolder[copy code]
   1:  Console.WriteLine("Spacial Folder(s):");
   2:  foreach (Environment.SpecialFolder value in Enum.GetValues(typeof(Environment.SpecialFolder)))
   3:  {
   4:      Console.WriteLine("{0}: {1}", value, Environment.GetFolderPath(value));
   5:  }

 

 

Visual Studio Platform 設定為 x86,在 Vista x64 下執行的結果是:

Spacial Folder(s):
Desktop: D:\HomeDisk\chicken\Desktop
Programs: C:\Users\chicken\AppData\Roaming\Microsoft\Windows\Start Menu\Programs
Personal: D:\HomeDisk\chicken\Documents
Personal: D:\HomeDisk\chicken\Documents
Favorites: D:\HomeDisk\chicken\Favorites
Startup: C:\Users\chicken\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup
Recent: C:\Users\chicken\AppData\Roaming\Microsoft\Windows\Recent
SendTo: C:\Users\chicken\AppData\Roaming\Microsoft\Windows\SendTo
StartMenu: C:\Users\chicken\AppData\Roaming\Microsoft\Windows\Start Menu
MyMusic: D:\HomeDisk\chicken\Music
DesktopDirectory: D:\HomeDisk\chicken\Desktop
MyComputer:
Templates: C:\Users\chicken\AppData\Roaming\Microsoft\Windows\Templates
ApplicationData: C:\Users\chicken\AppData\Roaming
LocalApplicationData: C:\Users\chicken\AppData\Local
InternetCache: C:\Users\chicken\AppData\Local\Microsoft\Windows\Temporary Internet Files
Cookies: C:\Users\chicken\AppData\Roaming\Microsoft\Windows\Cookies
History: C:\Users\chicken\AppData\Local\Microsoft\Windows\History
CommonApplicationData: C:\ProgramData
System: C:\Windows\system32
ProgramFiles: C:\Program Files (x86)
MyPictures: D:\HomeDisk\chicken\Pictures
CommonProgramFiles: C:\Program Files (x86)\Common Files

 

 

改成 x64 / Any CPU,在 Vista x64 下執行的結果是:

Spacial Folder(s):
Desktop: D:\HomeDisk\chicken\Desktop
Programs: C:\Users\chicken\AppData\Roaming\Microsoft\Windows\Start Menu\Programs Personal: D:\HomeDisk\chicken\Documents
Personal: D:\HomeDisk\chicken\Documents
Favorites: D:\HomeDisk\chicken\Favorites
Startup: C:\Users\chicken\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup
Recent: C:\Users\chicken\AppData\Roaming\Microsoft\Windows\Recent
SendTo: C:\Users\chicken\AppData\Roaming\Microsoft\Windows\SendTo
StartMenu: C:\Users\chicken\AppData\Roaming\Microsoft\Windows\Start Menu
MyMusic: D:\HomeDisk\chicken\Music
DesktopDirectory: D:\HomeDisk\chicken\Desktop
MyComputer:
Templates: C:\Users\chicken\AppData\Roaming\Microsoft\Windows\Templates
ApplicationData: C:\Users\chicken\AppData\Roaming
LocalApplicationData: C:\Users\chicken\AppData\Local
InternetCache: C:\Users\chicken\AppData\Local\Microsoft\Windows\Temporary Internet Files
Cookies: C:\Users\chicken\AppData\Roaming\Microsoft\Windows\Cookies
History: C:\Users\chicken\AppData\Local\Microsoft\Windows\History
CommonApplicationData: C:\ProgramData
System: C:\Windows\system32
ProgramFiles: C:\Program Files
MyPictures: D:\HomeDisk\chicken\Pictures
CommonProgramFiles: C:\Program Files\Common Files

 

 

再來看一段 code, 把所有的環境變數印出來:

印出所有的環境變數..[copy code]
   1:  Console.WriteLine("Environment Variable(s):");
   2:  IDictionary evs = Environment.GetEnvironmentVariables();
   3:  foreach (string key in evs.Keys)
   4:  {
   5:      Console.WriteLine("{0}: {1}", key, evs[key]);
   6:  }

 

 

x86:

 

Environment Variable(s):
Path: C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Program Files\Intel\DMIX
TEMP: C:\Users\chicken\AppData\Local\Temp
SESSIONNAME: Console
PATHEXT: .COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC
USERDOMAIN: CHICKEN-PC
PROCESSOR_ARCHITECTURE: x86
ProgramW6432: C:\Program Files
TRACE_FORMAT_SEARCH_PATH: \\NTREL202.ntdev.corp.microsoft.com\34FB5F65-FFEB-4B61-BF0E-A6A76C450FAA\TraceFormat
APPDATA: C:\Users\chicken\AppData\Roaming
windir: C:\Windows
LOCALAPPDATA: C:\Users\chicken\AppData\Local
CommonProgramW6432: C:\Program Files\Common Files
TMP: C:\Users\chicken\AppData\Local\Temp
USERPROFILE: C:\Users\chicken
ProgramFiles: C:\Program Files (x86)
CommonProgramFiles(x86): C:\Program Files (x86)\Common Files
FP_NO_HOST_CHECK: NO
HOMEPATH: \Users\chicken
COMPUTERNAME: CHICKEN-PC
ProgramData: C:\ProgramData
PROCESSOR_ARCHITEW6432: AMD64
USERNAME: chicken
NUMBER_OF_PROCESSORS: 4
PROCESSOR_IDENTIFIER: Intel64 Family 6 Model 23 Stepping 7, GenuineIntel
WecVersionForRosebud.1054: 2
SystemRoot: C:\Windows
ComSpec: C:\Windows\system32\cmd.exe
LOGONSERVER: \\CHICKEN-PC
DFSTRACINGON: FALSE
ProgramFiles(x86): C:\Program Files (x86)
VisualStudioDir: D:\HomeDisk\chicken\Documents\Visual Studio 2008
SystemDrive: C:
CommonProgramFiles: C:\Program Files (x86)\Common Files
PROCESSOR_LEVEL: 6
PROCESSOR_REVISION: 1707
PROMPT: $P$G
ALLUSERSPROFILE: C:\ProgramData
VS90COMNTOOLS: C:\Program Files (x86)\Microsoft Visual Studio 9.0\Common7\Tools\
PUBLIC: C:\Users\Public
OS: Windows_NT
HOMEDRIVE: C:

 

 

 

x64:

Environment Variable(s):
COMPUTERNAME: CHICKEN-PC
VisualStudioDir: D:\HomeDisk\chicken\Documents\Visual Studio 2008
HOMEPATH: \Users\chicken
LOCALAPPDATA: C:\Users\chicken\AppData\Local
USERNAME: chicken
PROCESSOR_ARCHITECTURE: AMD64
Path: C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Program Files\Intel\DMIX
CommonProgramFiles(x86): C:\Program Files (x86)\Common Files
ProgramFiles(x86): C:\Program Files (x86)
PROCESSOR_LEVEL: 6
LOGONSERVER: \\CHICKEN-PC
HOMEDRIVE: C:
USERPROFILE: C:\Users\chicken
SystemRoot: C:\Windows
TEMP: C:\Users\chicken\AppData\Local\Temp
WecVersionForRosebud.1054: 2
PUBLIC: C:\Users\Public
ALLUSERSPROFILE: C:\ProgramData
FP_NO_HOST_CHECK: NO
APPDATA: C:\Users\chicken\AppData\Roaming
DFSTRACINGON: FALSE
ProgramData: C:\ProgramData
PATHEXT: .COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC
OS: Windows_NT
CommonProgramFiles: C:\Program Files\Common Files
PROCESSOR_IDENTIFIER: Intel64 Family 6 Model 23 Stepping 7, GenuineIntel
ComSpec: C:\Windows\system32\cmd.exe
TRACE_FORMAT_SEARCH_PATH: \\NTREL202.ntdev.corp.microsoft.com\34FB5F65-FFEB-4B61-BF0E-A6A76C450FAA\TraceFormat
PROMPT: $P$G
SystemDrive: C:
PROCESSOR_REVISION: 1707
ProgramFiles: C:\Program Files
NUMBER_OF_PROCESSORS: 4
VS90COMNTOOLS: C:\Program Files (x86)\Microsoft Visual Studio 9.0\Common7\Tools\
TMP: C:\Users\chicken\AppData\Local\Temp
SESSIONNAME: Console
windir: C:\Windows
USERDOMAIN: CHICKEN-PC

 

有差異的地方我用紅色的字標出來了,看來程式還真的不能亂寫,那種寫好 RUN 了沒事就交差的人要注意了,哈哈.. 千萬不要雞婆自己湊路徑就是這樣... 其實同樣的狀況發生在好幾個地方,Win32 API 會重新導向, 32/64 用的是不同版本,Registry Key 也會重新導向,File System 也會重新導向...。

不過比較特別的是 c:\windows\system32 這目錄,文件上說會自動重新導向到 c:\windows\syswow64 下 (如果你是在 x64 環境下執行 x86 的程式),不過上面的例子抓到的路徑依舊是 c:\windows\system32 ( x86 / x64 都一樣 ),甚至是我在 x86 版本寫個檔案到 c:\windows\system32 下,回到 x64 的檔案總管看,它還真的在 c:\windows\system32\ 下...

不過當程式需要載入原本在 c:\windows\system32 下的檔案,或是呼叫到原本 windows 內建在這目錄下的 .dll / .exe 的話,還真的會被重新導向到 c:\windows\syswow64 ... 有興趣的朋友可以自己去這個目錄下逛一逛,該有的檔案都有,不過通通是 32 位元的版本..

所以裝 x64 有個缺點,C:\ 會變比較肥... 哈哈,因為什麼東西都擺兩份,Orz...

不過我用的方式都是土法鍊鋼,看起來像自己試出來的... 其實這樣不好,我是亂練的,大家不要學... 要寫 x64 程式的人,MSDN 這一個章節一定要看一下:

 

Programming Guide for 64-bit Windows

http://msdn.microsoft.com/en-us/library/bb427430(VS.85).aspx

 

這個章結的內容不多,翻一翻就看完了,裡面才是正解啊,不要再相信一些沒有根據的說法了... (咳,我又沒禿頭..),下次來講 IIS6 + x64 碰到的一堆靈異事件...






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