Re: [Libusbx-devel] [PATCH] Samples: Add FX2/FX3 firmware upload to RAM

[Orin E. <ori...@gm...>]

On Thu, Aug 9, 2012 at 4:57 PM, Jon Sturm <jon...@gm...> wrote:

> On Thu, Aug 9, 2012 at 3:01 AM, Markus <li...@ne...> wrote:
> > Hi Pete,
> >
> > my answers became a bit longer than intended. Here's my 5 cent,
> > but generally, I'd leave the decision to you:
> >
> >> Now, this being said, I don't have that much of an issue bumping the
> >> limit, but 4K seems awfully large for a file path. Would 512 bytes
> >> be OK with you?
> >
> > I'm perfectly ok with that.
>
> You should use PATH_MAX from limits.h period. POSIX says it should be
> there on *nix and it is also there on windows, being equal to
> MAX_PATH+1 iirc. Its 4K on linux but its also what the the libc is
> going to assume so you know you won't run into issues. Hardcoding
> anything smaller is just asking for issues especially on sample code
> that people are likely to just Copy/Paste into their projects.
>


It's only defined if _POSIX_ is set in the limits.h from Visual Studio 2010
and then it's defined to 512 so I wouldn't be counting on it being defined
sensibly for Windows (where MAX_PATH+1 is your best bet... unless of course
you prefix all your paths with "\\?\" and make sure all '/'s are switched
to '\'s when the limit is somewhere close to 32768 characters*.  Yes, you
can create paths in Windows greater than MAX_PATH long, though it's a
tossup whether any given application can handle them.)

I'd do something like the following:

#include <limits.h>
#if defined(WIN32) && !defined(PATH_MAX)
#define PATH_MAX (MAX_PATH+1)
#endif

and use PATH_MAX like you suggested.

Orin.

*for native APIs.  The shell APIs have the MAX_PATH limitation which is
another can of worms...