Re: GIOChannel and win32?

[Tor Lillqvist <tml iki fi>]

Tomasz Jankowski writes:
> [...] someone said [..] that GIOChannel may not work under the
> Microsoft Windows? Is that true, or not?

It depends.

If you are lucky, porting a GIOChannel-using program that works fine
on Linux or some other POSIX system to Windows is just a
recompilation. In reality, if you happen to use GIOChannels and
related machinery in a way that doesn't work the same way in the
Windows implementation, you will need some (usually minor) changes to
your code.

If you are specifically using GIOChannels for sockets (which I guess
is the most common use for them), to port just the socket code to
Windows you will at least need to ifdefify what headers you include:
On Windows, include <winsock2.h> (plus possibly <ws2tcpip.h>) instead
of the usual litany of <sys/types.h>, <sys/socket.h>, <netinet/in.h>,
<netinet/tcp.h>, <netdb.h> etc. Next you will have to ifdefify your
code as necessary for the differences in the socket APIs: At the very
least, you have to change close() calls on sockets to
closesocket(). And quite possibly other things as well: You cannot use
read() and write() on sockets on Windows, but have to use recv() and
send(). Socket calls don't set errno on Windows, instead get the error
code with WSAGetLastError(). Etc.

And then when you get to the GIOChannel stuff, there are differences
in how the implementations behave on Unix and Windows. For instance,
if you set up a watch on a GIOChannel for a socket on Windows, the
socket gets put into non-blocking mode. (Well, non-blocking mode
*should* be what you are using anyway on Unix too, as blocking mode
kinda defeats the whole idea of using GLib main loops and watches on
GIOChannels etc.)

Then there might be slight differences in what callbacks you get for
your watched sockets in what situations. In general, you will need to
do experimentation.

--tml