Re: RFC: Fixing fallback tempdir location on Win32

An aside, GetFolderPath() can result in a UNC path return, which might
complicate things about more if you use it.

Note the _d I had to use in File::HomeDir.

http://cpansearch.perl.org/src/ADAMK/File-HomeDir-1.00/lib/File/HomeDir/Windows.pm

Adam

On Thu, May 21, 2015 at 12:37 PM, Jan Dubois <[email protected]> wrote:
> On Thu, May 21, 2015 at 8:38 AM, David Golden <[email protected]> wrote:
>> We have various unsolved tickets (see end for links) about
>> File::Temp/File::Spec failing on Windows due to taint, where
>> File::Spec->tmpdir returns the root directory, which many Windows users
>> can't actually write to.  (Context: File::Spec checks -w on candidate temp
>> dirs, but that can be true on Windows, yet the ACLs can prevent files from
>> being written there. See perlport on -X operators.)
>
> I'm curious *why* tmpdir() would return the root directory. Normally
> %TMP% should be setup to point to the Temp directory inside the local
> APPDATA directory for regular users, or to %windir%/Temp when running
> as a service.
>
>> After discussions on #toolchain, I have two proposals:
>>
>> (1)  That File::Temp fall back to the following if it can't create a
>> temporary directory in the directory that is the result of
>> File::Spec->tmpdir:
>>
>>
>> File::Spec->catdir(Win32::GetFolderPath(Win32::CSIDL_LOCAL_APPDATA),q{Temp})
>
> Seems sensible to me, although I'm not sure what that returns for
> processes running as a service.
>
>> (2) That File::Spec::Win32 put that same path after environment variables
>> paths but before all existing fallback paths
>> (https://metacpan.org/source/SMUELLER/PathTools-3.47/lib/File/Spec/Win32.pm#L74-78)
>
> I just noticed the the GetTempPath() API will fall back to
> %USERPROFILE% if neither %TMP% nor %TEMP% are set. Maybe that variable
> should be checked as well, for consistency with other apps?
>
> https://msdn.microsoft.com/en-us/library/windows/desktop/aa364992%28v=vs.85%29.aspx
>
> Cheers,
> -Jan