Re: fork + socket -server fails

Wart schrieb:
While debugging a problem with tclhttpd on Fedora Core 5, I noticed the
following changed behavior.

If I use [fork] from either Expect or Tclx in combination with [socket
-server], the socket does not accept connections. This works fine on
Fedora Core 4.

Here is the sample script that I am using. On FC-4 I can telnet to port
8015 and the script prints out the expected "Accepted connection:"
message. On FC-5, nothing is printed. Turning off selinux and the
firewall do not fix the problem.

#!/usr/bin/tclsh

package require Expect

set port 8015

if {[fork]} {exit}

set serverSocket [socket -server myAccept $port]
puts "$serverSocket listening on port $port"

proc myAccept {args} {
puts "Accepted connection: $args"
}

vwait forever

FC-4 uses tcl-8.4.9 and expect-5.43.0. FC-5 uses tcl-8.4.12 and
expect-5.43.0. Has something changed between 8.4.9 and 8.4.12 that
might cause this, or is it more likely something changed in Fedora Core
that is causing the problem?

--Wart
I don't know about FC5, but start up your tclsh and take a look at the
tcl_platform array..., it could be that one build is threaded and the
other is not. (and threads do not play well with fork...)

Michael

.

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