Finding the MUSHclient version number from the server

Is there any way for the server to find out which version of MUSHclient a particular player is using? Perhaps some sort of negotiation option? Or maybe even a plugin?

The plugins I'm working on require the latest version of MUSHclient, but some players have tried to use them on older versions, and it would make it easier to troubleshoot if I could see at my end which version they're using.

I think a simple solution would just be, when you're making your plugin, have the version set to 3.0 or something like that. That way, any player who tries to use it will be able to. Also, make an announcement when you post your plugin advising users to upgrade. There is never harm in upgrading :)

Regards,
Forra

My plugins are built around the new subnegotiation callback functions, so any version of MUSHclient prior to 4.48 isn't going to work. I'm not sure what would happen if I set the version to 3.0, presumably the callback functions just wouldn't get called?


Oh I do tell them to upgrade, the problem is sometimes they don't fully read the announcement, and then I have to work out what they've done wrong. I was just wondering if there was a way to quickly see which version they're using, so that if they complain about it not working I can check in-game. I could even tie it into a "troubleshooting" dynamic help file then.

I still don't see why you would want that. If you set the version attribute in your plugin to the minimum version needed, MUSHclient will complain if a user tries to load the plugin, saying a newer version of MUSHclient is needed to use the plugin.

How is that not enough?

I would rather not have my MUSHclient version queryable, simply because that is a disaster waiting to happen. For one, servers with malicious intentions (or people compromising servers, for that matter) can then use version-specific exploits without a problem. Or you'll get other ugly stuff going on like the debacle that once happened (and still does) on the web regarding the useragent string.

Nope, server knowing the client is the most that should happen, specific versions are a no imo.

It's a version number, that's all. How on earth can that possibly compromise security?

If there's some huge security exploit in an earlier version of MUSHclient then a malicious server could just guess - knowing the version wouldn't make ANY difference whatsoever.

However when it comes to helping the user, the version number comes in useful. It would allow me to better tailor the hints and help files to each individual user.

Besides which, I'm not asking for it to be added, I'm asking if it can be done. It may be that it can be done via a plugin that works on most versions of MUSHclient, in which case the player could add that plugin as part of the package, and at least that one plugin should work even if the others don't.

If you don't like it, don't add it. That's the beauty of plugins.

You can try using the older OnPluginTelnetOption, which uses a specific option (102). Then implement a small protocol over that option to ask the client what its version is. It's available from version 4.31, which was released July 2008.

Thanks Twisol, good idea. But can the plugin actually find the version number? Is it stored as some sort of world variable?

Although even if not, maybe that'd be enough - a single plugin that checks for both protocol 102 and MSDP. If the plugin handshakes for 102 but not MSDP, that's a pretty good indication that they've added the plugin correctly but are using an older version of MUSHclient.

It sure can: the Version() function. When I run it, I get "4.51" back. You also have GetInfo(72), which does the same.

First step, add the "required version" to the plugin header. Then they can't even install the plugin if they have an early version. That is why it is there.

Next step, if you want to, use telnet negotiation to send the version back to the server, so the server can know that a) they have the plugin installed; and b) which version of MUSHclient they have (maybe add the plugin version as well).

I'm not totally sure why you need this, since when you release new versions of the plugin you simply upgrade the required version number if necessary.

And if something is added now that somehow (how?) tells every server the MUSHclient version, that won't be there for old versions anyway, so it doesn't achieve a huge amount.

Excellent, thanks.


I tested it previously by changing the version number on one of my plugins, closing the world and reopening it - the plugin seemed to simply disappear. But trying it again and looking more closely I see that it did also give an error message (but behind my session window).


Well it would at least let me see if they were using the latest version or not. If there was no response to the query I could just mark them as "old", and the dynamic help files could inform them in big red text that they need to update to the latest version of MUSHclient before downloading the custom plugins.

I'll probably just add it as a simple plugin though. Once I've got enough plugins I'll likely distribute a copy of MUSHclient with all of them preinstalled (along with the soundpack and graphical images) - but no doubt I'll continue adding further plugins in the future that'll require newer versions of MUSHclient, so it'll become increasingly useful to know which version people are using.


EDIT: I also just noticed that MXP has a version tag, so I guess that would be another option.

Just as a quick followup, I tried the MXP option and it works fine - all you need to do is send <VERSION> to the client, and it responds with:

<VERSION MXP="0.5" CLIENT=MUSHclient VERSION="4.51" REGISTERED=YES>

So basically it's already built into the client, as long as the server supports MXP.