MJL20080827 -- Update:  I Just realised that this is one of my top-visited pages and it's a totally disorganised and incongruent pile of... What's worse is, I've never updated it since the promised update back in March 2007!

Let me clear things up (and save you wading through the whole article): If you want remote access to your openSUSE desktop from a networked thin client, then forget about X11, XDMCP, VNC or tunneling X through SSH. Use the NX protocol. You'll need to do the following:

1. Install FreeNX on your openSUSE host. Some (slightly outdated, but usable) instructions are in Chapter 9 of the openSUSE 10.2 Reference manual. If you're using openSUSE 11.0 or newer, get the latest FreeNX package from the openSUSE Build Service (there are one-click install buttons)
2. Install an NX client on your remote terminal(s). Nomachine has free NX clients for Linux, Mac, Windows and Solaris (even some experimental ones for PlayStation 2 and Zaurus!). If your remote terminal is running openSUSE, you could alternatively get an open-source NX client from the build service (or ask yourself: I'm running X locally, so why don't I just use good ole SSH and X11?)
3. Configure your NX client to connect to the openSUSE host, then log in and enjoy!

The upshot: I've done this with a FreeNX server and Nomachine's NX client for Windows XP, and it all "just works", except maybe for some font issues with older X clients like emacs (install extra font packages from nomachine to fix that), and some transparency effect issues I noticed in kwin4, probably to do with X11 extensions missing in the NX client. Not a big deal.

Read the rest of this article for the boring background and laughable false-starts in my quest for remote desktops in X... <blush/>

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I don't know how many other people get this issue, but it comes up at my work a bit: Some co-worker asks me if I know of a tool to do such-and-such, and invariably I think “well, that's easy to do on Unix, but on Windows…”.

Then I remember Cygwin, and quickly find a Cygwin utility that does it, or can be scripted to do it with a small amount of work. So then co-worker asks if they can have a copy of this utility, and of course Cygwin is Free, so I say “sure, go download from www.cygwin.com.” Then they say, “yeah, but I don't want to install all of Cygwin, can't you just give me that one program?”

Well, the Cygwin command-line tools can be run from a Windows CMD.EXE shell, so this is quite possible to do. However, they all require the Cygwin POSIX layer, which at a minimum means I should also give them cygwin1.dll. But what other DLLs might the program use?

MJL2008-09-10T14:37+1000 Update: since this page gets a lot of hits, here's the quick answer: use cygcheck, i.e:

cygcheck grep

Find it under Happy hacker discovery #2. Keep reading if you're bored...

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It is useful to have different versions of the JVM installed, for a number of reasons:

• Different optimisation features from different JVM implementations
• Different language features from different JVM versions
• Java classes compiled with “Tiger” won't run in “Mantis”…

It is also useful to be able to quickly switch between installed JREs/JDKs depending on the task at hand.

If I'm hacking in Linux, the JPackage project provides a much nicer solution to this problem, and the Linux distro' I'm using (SUSE 10.0) uses JPackage. It'd be nice if there was an update-alternatives for Cygwin, but since there isn't I've come up with this hack.

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On the 32-bit Windows platform, JVM programs can only ever use up to about 1.5–1.6 GiB of memory in RAM per Java VM process. Allocating a heap size greater than this amount does not work. What's going on?

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When you first install cygwin and run bash, it'll usually display this error message:

Your group is currently "mkpasswd".  This indicates that
the /etc/passwd (and possibly /etc/group) files should be rebuilt.
See the man pages for mkpasswd and mkgroup then, for example, run
mkpasswd -l [-d] > /etc/passwd
mkgroup  -l [-d] > /etc/group
Note that the -d switch is necessary for domain users.

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In vanila SuSE 10.0, safely removing a USB frob can be a trial for non-root users. It's a shame, but I've found a fix that I'm 95% happy with.

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Further to my queries about WordPress' blog stats accuracy, I went googling for a free stats counter. This one's pretty good.

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I finally got fed up enough with Courier New to start searching for a legible, monospace font to use in jEdit. In Emacs, I'm particularly fond of the standard X font "misc-fixed" (though it's a little tough to tell appart O and 0 still). But for jEdit, the Java monospace font seems to map to Courier New in Windows, and to some God-awful font on Linux.

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I've been playing with customising jEdit a little bit, and decided to have a go at writing some simple date insertion macros. These perform the same work as some old elisp functions I wrote years ago in Emacs, to insert date/time stamps in various formats. In my .emacs file, I bind these functions to short-cut keys, and then use them for updating Changelogs in code and in offline journal entries.

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