[patch] cygcheck.cc update for cygpath()

[Christopher Faylor]

On Sun, Mar 09, 2008 at 04:14:40PM +0100, Corinna Vinschen wrote:
>On Mar  9 10:38, Christopher Faylor wrote:
>> On Sun, Mar 09, 2008 at 10:28:06AM +0100, Corinna Vinschen wrote:
>> >Bash as well as tcsh, as well as zsh (and probbaly pdksh, too) create an
>> >environment variable $PWD.  Maybe Cygwin should create $PWD for native
>> >apps if it's not already available through the parent shell.
>> 
>> I'd really rather not do that.  I don't think Cygwin should be polluting
>> the environment any more than it has to.  Even if this worked, it is
>> easily defeatable by setting a PWD environment variable before running
>> cygwin, so you'd have to keep track of this value through multiple
>> levels of process invocation.
>
>Nothing against adding a cygwin_internal for such a purpose, but how is
>that going to work?  Assuming the MingW application is called from a
>Cygwin application.  If the parent application's cwd is a long path, the
>MingW child gets its own cwd for apparent reasons.  If it loads the
>cygwin DLL dynamically, as cygcheck already does, how is that new
>invocation of the DLL supposed to know the cwd of the parent process? 

I guess I misunderstood.  I thought that the current working directory
could be derived through some complicated combination of Nt*() calls.

>Maybe I miss something, but I don't see how that could work without
>using another mechanism to transmit the cwd of the parent application to
>the child, and the environment seems like a pretty simple way to do it.
>
>What about just using PWD if it's set, but not to invent it in Cygwin if
>it doesn't exist?  I see two situations which probably cover 99% of the
>cases. 

The problem with environment variables are that they are under the
user's control.  If the user decides to modify PWD, then it can cause
issues.  That's why I was looking for a more foolproof solution.

That + I hate the thought of adding YA special environment variable for
Cygwin to worry about.  A "real" "OS" would never consider passing stuff
around in environment variables.

cgf