Subject: Re: socklen_t type
From: "Yaakov (Cygwin/X)" <yselkowitz@users.sourceforge.net>
To: cygwin <cygwin@cygwin.com>
Date: Fri, 29 Jul 2011 17:30:52 -0500
In-Reply-To: <20110729202330.GE13084@calimero.vinschen.de>
References: <4E330A4C.90706@redhat.com>	 <20110729202330.GE13084@calimero.vinschen.de>
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On Fri, 2011-07-29 at 22:23 +0200, Corinna Vinschen wrote:
> On Jul 29 13:30, Eric Blake wrote:
> > Is there any specific reason why socklen_t on cygwin is int instead
> > of uint32_t, like it is on Linux?
> 
> Other than history?  No, I don't think so.  But I also don't think
> it's worth the effort.  All the underlying Windows functions typically
> use int rather than uint32_t, and even the Linux man page states:
> 
>   The optlen argument of getsockopt() and setsockopt() is in reality an
>   int [*] (and this is what 4.x BSD and libc4 and libc5 have).  Some
>   POSIX confusion resulted in the present socklen_t, also used by glibc.

FWIW, I am aware of the following packages which are affected by the
difference:

kdebase-runtime
libgcrypt
libunique

But POSIX says[1]:

> The <sys/socket.h> header shall define the socklen_t type, which is an
> integer type of width of at least 32 bits...
> 
> To forestall portability problems, it is recommended that applications
> not use values larger than 2^31 -1 for the socklen_t type.

That would seem to allow either 'uint32_t' or 'int', so we're not wrong,
and its the aforementioned applications' fault for making Linux
assumptions.


Yaakov

[1]
http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_socket.h.html


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