OpenEuphoria

Re: getenv

• Posted by Bernie Ryan <xotron at bluefrog.c??> May 30, 2008
• 665 views

CChris wrote:
> 
> Jeremy Cowgar wrote:
> > 
> > Kenneth Rhodes wrote:
> > > 
> > > If the problem is under Windows, shouldn't that
> > > be where the fix is applied?
> > >
> > 
> > Yes, that would be ideal, but I do think that is possible. Windows does not
> > provide the means (that I can find) to tell if an environment variable is
> > set
> > with an empty value or unset. For both of those cases, it returns the same
> > value.
> > 
> > So, we have two options. #1 dumb down the Linux version so that Euphoria is
> > consistent or document that getenv() works differently on Windows and Linux
> > (which is not my favorite option).
> >  
> > Maybe someone else knows a function call we can make in the win/dos api?
> > 
> > --
> > Jeremy Cowgar
> > <a href="http://jeremy.cowgar.com">http://jeremy.cowgar.com</a>
> 
> It will never work under DOS:
> in the environment segment, an env var is coded as follows:
> 
> <var-name>=<value>0
> 
> The 0 is the separator between two variable descriptions. From this, it would
> follow that an empty string would be coded as
> 
> <var-name>=00
> 
> But 00 marks the end of the environment table.
> 
> And, since I strongly suspect M$ uses the same representation of an env block
> under DOS and Windows, there is nothing as an env string with a null value
> under
> Windows.
> 
> So how  did George get one? Simply because he entered it. For any operation
> on environment, 0 is treated as a variable separator, not as a terminating \0.
> So there is no inconsistency nor miracle. He didn't get it for long I bet.
> 
> CChris

DWORD GetEnvironmentVariable(
  LPCTSTR lpName,  // address of environment variable name
  LPTSTR lpBuffer, // address of buffer for variable value
  DWORD nSize      // size of buffer, in characters
);


Bernie

My files in archive:
WMOTOR, XMOTOR, W32ENGIN, MIXEDLIB, EU_ENGIN, WIN32ERU, WIN32API 

Can be downloaded here:
http://www.rapideuphoria.com/cgi-bin/asearch.exu?dos=on&win=on&lnx=on&gen=on&keywords=bernie+ryan