MNO - Whilst knocking up a PocketPC application today PocketICS, I have noticed some weirdness with fileevent (or socket or fconfigure... I'm not sure where to look).
I can minimally demonstrate this with the following code snippet (adapted from the telnet page), which tries to connect to an internet chess server:-
#! /bin/sh
# THIS LINE MUST BE HERE \
exec tclsh "$0" ${1+"$@"}
package require Tk
proc telnet {{server localhost} {port 23}} {
global sock
set sock [socket $server $port]
fconfigure $sock -buffering none -blocking 0
fileevent $sock readable [list fromServer $sock]
global closed
vwait closed($sock)
unset closed($sock)
}
proc toServer {} {
global comm sock
puts $sock $comm
set comm ""
update
}
proc fromServer {sock} {
set data x
while {[string length $data]} {
set data [read $sock 4096]
if {[eof $sock]} {
disconnect $sock
return
}
if {[string length $data]} {
.t insert end $data
.t see end
}
}
}
proc disconnect {sock} {
global closed
close $sock
set closed($sock) 1
}
pack [text .t -font {Tahoma 7} -height 20 -width 40] [entry .e -textvariable comm]
bind .e <Return> toServer
telnet chessclub.com 5000Running this piece of code on either a Linux system (Tcl/Tk version 8.4b2) or Windows 2000 system (ActiveTcl 8.4.0) works exactly as expected - I get to the login prompt, can enter my handle in the entry box and this gets sent to the server which then prompts me for the password.
If, however, I run this on my PocketPC, (using the 8.4.3 tcl/tk on the Windows/CE page), I get the login prompt (i.e., proving that the fileevent has fired), and can send my handle, but I never see the password prompt in the text box (i.e., the fileevent doesn't seem to fire again).
The strange thing is that if I snoop the connection (my PocketPC internet connection is via my Linux machine) using tcpdump, I can see the handle being sent, and the response including the password prompt being sent back by the server. I can then even enter the password in the entry box, and see it go to the server and the login session continues fine. The fileevent never seems to fire again though, so all that I ever seem to get in my text box is the first set of output up to and including the login prompt.
Any ideas? Is this a bug in the Windows/CE Tcl/Tk version?
Could this be related to Tcl bug #719790 (fcopy -command hangs in Win NT4)? It looks like that bug only affects Tclkit, not tclsh - but somehow it sounds similar... -jcw
escargo - Could you use sockspy to get another view of what is happening? (I don't know if it would be more useful than tcpdump.)
MNO - I don't think running sockspy on the linux node would help much since, as you note, I've got tcpdump running there. I wondered about running it on the PocketPC end but, of course, it is pure Tcl and relies on fileevent itself. I may try it there anyway tonight, in case it behaves differently, but if there is a bug then sockspy is probably going to be affected too... There looks to be one difference in the fconfigure behaviour of sockspy (it sets -translation binary which i don't). I don't know if this will make a difference or not. i did try the above code with -encoding binary set, but this didn't seem to change the behaviour any.