[PATCH] Allow os/backtrace.c to compile on Solaris 10.

[Mark Kettenis]

> From: pekane52 at gmail.com
> Date: Tue,  9 Nov 2010 17:40:21 -0600
> 
> From: Patrick E. Kane <pekane52 at gmail.com>
> 
> 
> Signed-off-by: Patrick E. Kane <pekane52 at gmail.com>
> ---
>  os/backtrace.c |    5 +++++
>  1 files changed, 5 insertions(+), 0 deletions(-)
> 
> diff --git a/os/backtrace.c b/os/backtrace.c
> index 7ca6dab..1050d77 100644
> --- a/os/backtrace.c
> +++ b/os/backtrace.c
> @@ -25,6 +25,11 @@
>  #include <dix-config.h>
>  #endif
>  
> +#if defined(sun) && defined(__SVR4)
> +# include <unistd.h>
> +# include <errno.h>
> +#endif
> +
>  #include "os.h"
>  #include "misc.h"

It should be fine to just include these headers unconditionally.  That
would reduce the #ifdef clutter a bit.