Re: sockets /network programming Requirements

From: williamkempf_at_[hidden]
Date: 2001-07-30 14:19:26

I'm interested in this library, and if help is needed I'll lend what 
ever time I can spare.  My comments on the document:

* Exceptions should not be used for precondition violations.  
Assertions and/or error returns should be used instead in this case.

* The "must be portable" requirement may prove more than vexing. Unix 
programmers rely heavily on select(), while Windows programmers can 
only make very limited use of this and rely almost completely on 
asynchronous routines not available to Unix programmers.  The 
simplest way to insure portability is to support only blocking i/o 
with very limited ability to check for available data, but this can 
severely complicate coding.  A possibly better solution is to provide 
a callback mechanism similar to the asynchronous routines in Win32 
that do not rely on Win32 specific WndProc mechanisms.  (I never 
understood why I/O was tied to a GUI object in Win32 asynchronous 
routines.) Such an interface could be coded portably using threads on 
any platform, though the design will be much more complicated.

* One thing I often see done wrong when it comes to "reducing 
preconditions" is overloading methods that connect a socket for 
numerous ways of specifying the address/port pair.  There should be 
two seperate object types, InetAddress and InetPort (pick your name 
for these) that can be constructed with the various options such as 
URL, IP, friendly name, etc.  The connection routines should only 
take these as parameters.  This vastly simplifies much of the user 
coding, as well as maintenance required if some new way of specifying 
these comes into existence later.

* I don't think FTP, HTTP or other protocol client/server classes 
should even be considered for inclusion, at least in a first 
submission.

--- In boost_at_y..., Iain.Hanson_at_u... wrote:
>      Hi folks,
>      
>      Beman has done an initial set of requirements for this, which 
I have 
>      put in boost files/socket2/Sock-req.html.
>      
>      We'd welcome your feed back and comments.
>      
>      /ikh