Date: Fri, 18 Dec 2009 11:10:32 +0100
From: Corinna Vinschen <corinna-cygwin@cygwin.com>
To: cygwin@cygwin.com
Subject: Re: cygwin_conv_path() documentation RFE
Message-ID: <20091218101032.GH8059@calimero.vinschen.de>
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On Dec 17 19:29, Warren Young wrote:
> On this page
> 
> 	http://cygwin.com/1.7/cygwin-api/func-cygwin-conv-path.html
> 
> the size parameter should say whether it's measured in bytes or
> characters.
> 
> For instance, if I pass CCP_POSIX_TO_WIN_W for the first parameter
> and a pure ASCII file name for the 'from' parameter, it's obvious
> the 'to' buffer needs to be at least 2x the size of 'from'.  The
> question the docs don't answer is whether I should pass >=
> 2*(strlen(from)+1) for size or >= strlen(from)+1?

I really thought that would be clear from the description of what
happens if size is 0:

  "If size is 0, cygwin_conv_path just returns the required buffer size
   in bytes."

and the subsequent example code which uses the size returned by
cygwin_conv_path in a call to malloc and then, unchanged in the next
cygwin_conv_path call.  I suggest to implement it as in the example.
Otherwise you will potentially need a buffer of 64K to return the
path in it.  Alternatively just use the cygwin_create_path function
which will malloc the buffer for you.

I'll change the description so that the value of "size" should be clear
from the beginning.


Corinna

-- 
Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

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