Re: XEmacs checking network connection (problem)
robert delius royar wrote:
I have been having some connection problems lately and as a result
discovered that my XEmacs when it starts appears to need a connection to the
internet. Once it is running, the connection can go down without a problem.
But if the connection is down when XEmacs starts, it waits until the
connection is back up before it opens its initial Frame.
I believe this may be because I use a context resumption program, that one
or more of my files are html, that psgml is required, AND that *psgml
requires sendmail.el*
Could this cause XEmacs to wait for a connection before displaying its
initial frame? If so, is it essential that psgml-html.el require
sendmail.el?
What other functions/variables might I need to watch for in my startup file
that would cause the busy wait on the net?
The error does not occur when XEmacs is started without its startup file.
Historically, this problem has occurred as a result of host name
canonicalisation, due to the use of gethostbyname() or getaddrinfo().
Basically, XEmacs may end up performing a DNS lookup on your hostname.
The two most common reasons for the DNS lookup are:
1. There isn't an entry for your host in /etc/hosts, or it doesn't
include the host's FQDN (fully-qualified domain name, e.g.
yourhost.yourdomain.com).
2. Your system's getaddrinfo() function tries to obtain IPv6
information, which it can't get from /etc/hosts.
I can't say for sure whether this really is your problem, but most
"XEmacs hangs when offline" problems are due to DNS lookups for
whatever reason.
You may be able to confirm this with a process tracing tool (e.g.
strace, ltrace) or debugger (e.g. gdb), or with a network sniffer
(e.g. tcpdump).
--
Glynn Clements <glynn.clements(a)virgin.net>