Re: [boost] [filesystem] home_directory_path

Subject: Re: [boost] [filesystem] home_directory_path
From: Marsh Ray (marsh_at_[hidden])
Date: 2010-10-18 16:22:41

On 10/18/2010 09:58 AM, Jeff Flinn wrote:
> In looking at implementing a portable home_directory_path function a few
> questions arise.
>
> Based on http://en.wikipedia.org/wiki/Home_directory, POSIX and other
> UNIX flavors 'appear' to be a straight forward use of the "HOME"
> environment variable. Does anyone have any experience where the "HOME"
> variable is not the proper source of the user's home directory?
>
> Windows NT and above have the "USERPROFILE" environment variable. Using
> this would be the easiest to use. But I've seen discussion that this may
> not always be properly defined, in particular if the user has reset
> their home directory to a non-system drive.

I wouldn't count on it for anything critical.

> I haven't tracked down it's
> availability on WinCE. Does anyone have experience with this platform?
>
> There is the windows GetUserProfileDirectory api function also available
> since NT4.

That's a the call to use if indeed you want "the root directory of the 
specified user's profile".
http://msdn.microsoft.com/en-us/library/bb762280.aspx

_But it's important to be prepared for case where the code is executing 
as a user who does not actually have a profile on the machine!_

You might be better off calling SHGetFolderPath with a CSIDL value like 
CSIDL_APPDATA.
http://msdn.microsoft.com/en-us/library/bb762181.aspx
http://msdn.microsoft.com/en-us/library/bb762494.aspx

> This is in the Userenv.lib/dll, obviously adding a link
> dependancy. How are these sorts of system link dependencies handled?
> Through bjam? Or is it acceptable/better to use #pragma
> comment(lib,"Userenv.lib")?
>
> In looking at some client code using home_directory_path, I see that
> they generally are looking for the user's Desktop directory(Mac &
> Windows). Obviously this only makes sense on GUI platforms. The issue
> with merely getting this path via home_directory_path() / "Desktop" is
> IIRC, that at least on windows "Desktop" is localized and may not exist
> with that name on non-english localized systems. Windows has the
> SHGetFolderPath api. I need to look into Mac's native support. Any
> thoughts on the general usefulness of a portable desktop_directory_path?

It seems to me like if you're going to work with a "Desktop", you're 
going to need a variety of platform specific logic to deal with things 
like file types, icons, app associations, etc. You'd need a real 
platform UI layer. So I don't think a single function to just find the 
path is likely to be useful to many.

- Marsh