就在我以为我已经看到了所有 Windows 路径问题时,我现在遇到了一个只有在使用“/”(正斜杠)作为路径分隔符时才会失败的情况:
C:\temp\tcbugs>mkdir "dir1 with spaces"
C:\temp\tcbugs>echo hi > "dir1 with spaces"\foo.txt
C:\temp\tcbugs>type "dir1 with spaces\foo.txt"
hi
C:\temp\tcbugs>type "dir1 with spaces/foo.txt"
The system cannot find the file specified.
特别有趣的是,它似乎特定于 cmd.exe shell 而不会出现在 PowerShell 中(大概也不会出现在 win32 API 中):
PS C:\temp\tcbugs> type 'dir1 with spaces/foo.txt'
hi
另一个有趣的地方是,使用“cd”更改目录并使用“/”用作 cmd.exe 的路径分隔符确实有效:
C:\temp\tcbugs>mkdir dir2_no_spaces
C:\temp\tcbugs>cd ./dir2_no_spaces
C:\temp\tcbugs\dir2_no_spaces>cd ..
然而,我在网上或 MSDN 经常引用的文档中都找不到关于这个特定问题的任何引用资料:
Naming Files, Paths, Namespaces
这让我不禁要问:为什么会发生这种情况,是否有记录这一怪癖的权威来源?
更新:
dbenham 指出无论目录名称中是否有空格,问题都会存在,因此在标题和问题正文中删除了对它的引用。还添加了一个有效的“cd ./”示例,而其他命令则无效。
最佳答案
编辑以删除意见
无论 Windows CMD.EXE 是否应该支持路径中的正斜杠,事实是它有时有效,有时无效,有时它似乎有效但给出错误的结果 - 也称为错误。
是时候进行一些实验了:-)
所有测试都在 Vista 上运行
C:\>md "c:/temp/"
C:\>REM The forward slash works with MD!
C:\>echo hello world 1>>"c:/temp/test.txt"
C:\>REM Redirection works with forward slashes!
C:\>type "c:\temp\test.txt"
hello world
C:\>REM Of course TYPE works with back slashes
C:\>type "c:/temp/test.txt"
The system cannot find the file specified.
C:\>REM But forward slash version fails
C:\>type "c:/temp\test.txt"
hello world
C:\>REM But TYPE works with forward slash as long as last slash is back slash
C:\>dir "c:/temp/test.txt"
Volume in drive C is OS
Volume Serial Number is EE2C-5A11
Directory of c:\temp
File Not Found
C:\>REM Note how DIR lists the directory with a \, yet fails to find any files
C:\>dir "c:/temp/*"
Volume in drive C is OS
Volume Serial Number is EE2C-5A11
Directory of c:\temp
File Not Found
C:\>REM DIR Still fails with forward slashes
C:\>dir "c:/temp/"
Volume in drive C is OS
Volume Serial Number is EE2C-5A11
Directory of c:\temp
05/09/2012 09:58 PM <DIR> .
05/09/2012 09:58 PM <DIR> ..
05/09/2012 09:58 PM 13 test.txt
1 File(s) 13 bytes
2 Dir(s) 337,001,615,360 bytes free
C:\>REM But forward slash works if no file is specified!
C:\>dir "c:/temp\test.txt"
Volume in drive C is OS
Volume Serial Number is EE2C-5A11
Directory of c:\temp
05/09/2012 09:58 PM 13 test.txt
1 File(s) 13 bytes
0 Dir(s) 337,001,615,360 bytes free
C:\>REM And DIR works with forward slash as long as last slash is back slash
C:\>REM Now add another folder to the path hierarchy
C:\>md "c:/temp/temp/"
C:\>REM Still can create folder using forward slashes
C:\>copy "c:/temp/test.txt" "c:/temp/temp/"
The system cannot find the file specified.
0 file(s) copied.
C:\>REM Failed to copy with forward slashes
C:\>copy "c:/temp\test.txt" "c:/temp/temp/"
1 file(s) copied.
C:\>REM But forward slash works if last slash before file name is back slash
C:\>REM Rerun some past tests
C:\>type "c:/temp/test.txt"
The system cannot find the file specified.
C:\>REM Good - it still fails
C:\>dir "c:/temp/test.txt"
Volume in drive C is OS
Volume Serial Number is EE2C-5A11
Directory of c:\temp
05/09/2012 09:58 PM 13 test.txt
1 File(s) 13 bytes
0 Dir(s) 337,001,615,360 bytes free
C:\>REM What is going on?! :( Why did that seem to work now?
C:\>REM More on that later.
C:\>REM Now test the new folder
C:\>type "c:/temp/temp/test.txt"
The system cannot find the file specified.
C:\>REM Forward slashes still fail with TYPE
C:\>type "c:/temp/temp\test.txt"
hello world
C:\>REM But forward slash still works as long as last slash is back slash
C:\>dir "c:/temp/temp/*"
Volume in drive C is OS
Volume Serial Number is EE2C-5A11
Directory of c:\temp\temp
File Not Found
C:\>REM Again, forward slashes fail, but directory path is listed properly
C:\>dir "c:/temp/temp/"
Volume in drive C is OS
Volume Serial Number is EE2C-5A11
Directory of c:\temp\temp
05/09/2012 09:58 PM <DIR> .
05/09/2012 09:58 PM <DIR> ..
05/09/2012 09:58 PM 13 test.txt
1 File(s) 13 bytes
2 Dir(s) 337,001,615,360 bytes free
C:\>REM And again it works if no file is specified
C:\>dir "c:/temp/temp\test.txt"
Volume in drive C is OS
Volume Serial Number is EE2C-5A11
Directory of c:\temp\temp
05/09/2012 09:58 PM 13 test.txt
1 File(s) 13 bytes
0 Dir(s) 337,001,615,360 bytes free
C:\>REM Again forward slashes work as long as last slash is back slash
这是一个清楚地证明错误的案例。
c:\>dir /s /a-d temp
Volume in drive C is OS
Volume Serial Number is EE2C-5A11
Directory of c:\temp
05/10/2012 08:01 AM 13 test.txt
1 File(s) 13 bytes
Directory of c:\temp\temp
05/10/2012 07:57 AM 10 test.txt
1 File(s) 10 bytes
Total Files Listed:
2 File(s) 23 bytes
0 Dir(s) 337,325,191,168 bytes free
c:\>REM Note the different file sizes found in each directory
c:\>dir "c:/temp/test.txt"
Volume in drive C is OS
Volume Serial Number is EE2C-5A11
Directory of c:\temp
05/10/2012 07:57 AM 10 test.txt
1 File(s) 10 bytes
0 Dir(s) 337,325,191,168 bytes free
c:\>REM It is listing the wrong file!
可以争论 Windows CMD 是否“应该”支持正斜杠。但最后的结果是一个错误!即使在使用正斜杠时出现操作错误,Windows 也不应给出该结果。
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