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Re: tcsh path conversion messed up? [was: strange shell output using tcsh under Cygwin]




On 2017-11-06 14:59, Will Parsons wrote:
> Will Parsons wrote:
>> I asked about what I thought was a shell scripting problem:
>>
>> Will Parsons wrote:
>>> Under Unix-type platforms, checking on what the PATH variable is set to is
>>> pretty easy - I typically use "env" and the displayed value of PATH is easily
>>> parsed by eye.  Under Cygwin/Windows, one can do the same, but the value of
>>> PATH is more likely to be considerably more complicated and harder for a
>>> human to parse.  For example, this is what I see on my local machine under
>>> Cygwin:
>>>
>>>    PATH=/usr/local/bin:/usr/bin:/c/Windows/system32:/c/Windows:/c/Windows/system32/wbem:/c/ProgramData/Oracle/Java/javapath:/c/Program Files/Common Files/Microsoft Shared/Windows Live:/c/Program Files (x86)/Common Files/Microsoft Shared/Windows Live:/c/Program Files/Dell/DW WLAN Card:/c/Program Files (x86)/Intel/iCLS Client:/c/Program Files/Intel/iCLS Client:/c/Windows/System32/WindowsPowerShell/v1.0:/c/Program Files/WIDCOMM/Bluetooth Software:/c/Program Files/WIDCOMM/Bluetooth Software/syswow64:/c/Program Files (x86)/Windows Live/Shared:/c/Program Files (x86)/Bazaar:/c/Program Files (x86)/QuickTime/QTSystem:/c/cygwin/home/william/bin:/c/ezwinports/bin:/c/Program Files (x86)/PuTTY:/usr/lib/lapack:/usr/sbin:/c/msys/1.0/local/bin
>>
>> This was a cut/paste, so I would be sure of not making a mistake.  The PATH
>> looks completely reasonable to me, but...
>>
>>> I thought it would be nice to write a simple script to make this more
>>> comprehensible by breaking the path into separate lines, and so wrote the
>>> following trivial script:
>>>
>>>    #!/bin/sh
>>>    echo $PATH | tr ':' '\n'
>>>
>>> Oddly though, it does not give the expected results under Cygwin.  Running
>>> this script under Cygwin under my normal interactive script (tcsh) yields the
>>> following:
>>>
>>>    % ./path
>>>    /usr/local/bin
>>>    /usr/bin
>>>    /bin
>>>    /usr/sbin
>>>    /c/Windows/system32
>>>    /c/Windows
>>>    /c/Windows/system32/wbem
>>>    /c/ProgramData/Oracle/Java/javapath
>>>    /c/Program
>>>    Files/Common
>>>    Files/Microsoft
>>>    Shared/Windows
>>>    Live
>>>    /c/Program
>>>    Files
>>>    (x86)/Common
>>>    Files/Microsoft
>>>    Shared/Windows
>>>    Live
>>>    /c/Program
>>>    Files/Dell/DW
>>>    WLAN
>>>    Card
>>>    /c/Program
>>>    Files
>>>    (x86)/Intel/iCLS
>>>    Client
>>>    /c/Program
>>>    Files/Intel/iCLS
>>>    Client
>>>    /c/Windows/System32/WindowsPowerShell/v1.0
>>>    /c/Program
>>>    Files/WIDCOMM/Bluetooth
>>>    Software
>>>    /c/Program
>>>    Files/WIDCOMM/Bluetooth
>>>    Software/syswow64
>>>    /c/Program
>>>    Files
>>>    (x86)/Windows
>>>    Live/Shared
>>>    /c/Program
>>>    Files
>>>    (x86)/Bazaar
>>>    /c/Program
>>>    Files
>>>    (x86)/QuickTime/QTSystem
>>>    /c/cygwin/home/william/bin
>>>    /c/ezwinports/bin
>>>    /c/Program
>>>    Files
>>>    (x86)/PuTTY
>>>    /usr/lib/lapack
>>>
>>> Clearly the path is being broken using spaces as well as colons.
>>>
>>> Even thoush the shell script itself explicitly specifies "/bin/sh", the
>>> result seems to depend on the shell being used to invoke it.  Using Cugwin
>>> bash, the same script results in the following:
>>>
>>>    sothis$ ./path
>>>    /usr/local/bin
>>>    /usr/bin
>>>    /c/Windows/system32
>>>    /c/Windows
>>>    /c/Windows/system32/wbem
>>>    /c/ProgramData/Oracle/Java/javapath
>>>    /c/Program Files/Common Files/Microsoft Shared/Windows Live
>>>    /c/Program Files (x86)/Common Files/Microsoft Shared/Windows Live
>>>    /c/Program Files/Dell/DW WLAN Card
>>>    /c/Program Files (x86)/Intel/iCLS Client
>>>    /c/Program Files/Intel/iCLS Client
>>>    /c/Windows/System32/WindowsPowerShell/v1.0
>>>    /c/Program Files/WIDCOMM/Bluetooth Software
>>>    /c/Program Files/WIDCOMM/Bluetooth Software/syswow64
>>>    /c/Program Files (x86)/Windows Live/Shared
>>>    /c/Program Files (x86)/Bazaar
>>>    /c/Program Files (x86)/QuickTime/QTSystem
>>>    /c/cygwin/home/william/bin
>>>    /c/ezwinports/bin
>>>    /c/Program Files (x86)/PuTTY
>>>    /usr/lib/lapack
>>>    /usr/sbin
>>>    /c/msys/1.0/local/bin
>>
>> I have just rebooted my Windows machine and see that in constrast to what I
>> wrote above, the value of PATH under tcsh shows up as:
>>
>>    PATH=/usr/local/bin:/usr/bin:/bin:/usr/sbin:/c/Windows/system32:/c/Windows:/c/Windows/system32/wbem:/c/ProgramData/Oracle/Java/javapath:/c/Program:Files/Common:Files/Microsoft:Shared/Windows:Live:/c/Program:Files:(x86)/Common:Files/Microsoft:Shared/Windows:Live:/c/Program:Files/Dell/DW:WLAN:Card:/c/Program:Files:(x86)/Intel/iCLS:Client:/c/Program:Files/Intel/iCLS:Client:/c/Windows/System32/WindowsPowerShell/v1.0:/c/Program:Files/WIDCOMM/Bluetooth:Software:/c/Program:Files/WIDCOMM/Bluetooth:Software/syswow64:/c/Program:Files:(x86)/Windows:Live/Shared:/c/Program:Files:(x86)/Bazaar:/c/Program:Files:(x86)/QuickTime/QTSystem:/c/cygwin/home/william/bin:/c/ezwinports/bin:/c/Program:Files:(x86)/PuTTY:/usr/lib/lapack
>>
>> This doesn't look right, and would explain the strange shell output I
>> reported.  (The value of PATH under bash looks normal.)  Did the installation
>> of tcsh somehow get corrupted?  I don't remember a particularly recent update
>> to tcsh.
> 
> Another bit of info - I just noticed that the value of the (t)csh shell
> variable 'path' is:
> 
>     (/usr/local/bin /usr/bin /bin /usr/sbin /c/Windows/system32 /c/Windows /c/Windows/system32/wbem /c/ProgramData/Oracle/Java/javapath /c/Program Files/Common Files/Microsoft Shared/Windows Live /c/Program Files (x86)/Common Files/Microsoft Shared/Windows Live /c/Program Files/Dell/DW WLAN Card /c/Program Files (x86)/Intel/iCLS Client /c/Program Files/Intel/iCLS Client /c/Windows/System32/WindowsPowerShell/v1.0 /c/Program Files/WIDCOMM/Bluetooth Software /c/Program Files/WIDCOMM/Bluetooth Software/syswow64 /c/Program Files (x86)/Windows Live/Shared /c/Program Files (x86)/Bazaar /c/Program Files (x86)/QuickTime/QTSystem /c/cygwin/home/william/bin /c/ezwinports/bin /c/Program Files (x86)/PuTTY /usr/lib/lapack)
> 
> I can see that if one simply translates spaces to colons to derive $PATH from
> $path, there might be problems...

Regardless of from which shell and how I execute your path script - as "./path",
"source path", or ". path", the result is the same as expected, as it is a
simple Unix pipeline with two commands and an environment variable, and no shell
dependencies.

[Sorry if I'm unclear below, but it's been years since I last used csh under
Solaris, and it wasn't available on most systems until ported to Linux.]

In csh, "PATH" is a standard Unix environment variable whose value is a colon
separated directory list, and "path" is a shell wordlist kept synchonized with
"PATH".
To list the wordlist entries with embedded spaces in csh, quote the variable
name with the :q modifier in a foreach loop wordlist, and you get the desired
result as easily as in your sh script [trimmed and ...s redacted]:

.......% foreach p ( $path:q )
foreach?	echo $p
foreach? end
/mnt/c/.../bin
/usr/local/bin
/usr/local/sbin
/usr/bin
/usr/sbin
/sbin
/usr/lib/lapack
/mnt/c/.../AppData/Local/Microsoft/WindowsApps
/mnt/c/Program Files (x86)/Microsoft SDKs/TypeScript/1.0
/mnt/c/Program Files/Microsoft SQL Server/120/Tools/Binn
/mnt/c/Program Files/Microsoft SQL Server/110/Tools/Binn
/mnt/c/WINDOWS/System32/WindowsPowerShell/v1.0
/mnt/c/WINDOWS/System32/Wbem
/mnt/c/WINDOWS/system32
/mnt/c/WINDOWS

Is your Cygwin install (partially?) outdated?
Download and run setup-x86{_64} to update everything and retry your tests.

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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