Arch linux optional dependencies

Arch Linux and optional dependencies

So while the plugins for Python and Perl are loaded correctly, the Tcl plugin is not. In fact, python2 and perl packages are installed on my system, while tcl package is not. Installing tcl fixes the problem. Before installing tcl , I get:

ldd /usr/lib/xchat/plugins/tcl.so | grep tcl libtcl8.5.so => not found 

ldd /usr/lib/xchat/plugins/tcl.so | grep tcl libtcl8.5.so => /usr/lib/libtcl8.5.so (0x00007fceba533000) 

pacman -Qi xchat . Optional Deps : enchant: for spell checking support tcl: for tcl plugin python2: for python plugin . 

1. The error message I get when running XChat without tcl installed is clearly visible in the GUI, in the same place where messages are displayed.
2. My question can also be reworded in the following way: why XChat, despite having clearly been built with —enable-tcl or equivalent passed to the configure script, can be installed without a mandatory dependency on the tcl package? If one don’t want tcl , he should use —disable-tcl .

EDIT. I opened a thread on the Arch Linux forum, but I didn’t get a satisfying answer. So I checked Debian and Gentoo, and it seems they don’t have this problem.

I forgot to say that despite that error message XChat is working great anyway. I don’t think I need plugins at all.

I may be wrong, but software should be installed in such a way that the user should not be alarmed by error messages, even if they are relatively innocuous.

Isn’t that message visible only when you launch xchat via the command line? Wouldn’t most users run it from a menu/icon thing?

2 Answers 2

It’s mostly a matter of complexity and how people choose to invest their time.

If you wanted an XChat binary package that doesn’t show any warnings/errors related to missing libraries for plugins, you have essentially two choices:

• only include/configure «vital» plugins, and add hard dependencies for what those things require
• include each and every plugin available, and add hard dependencies for what those things require

The first option leaves you with an XChat package that doesn’t have a lot of features at all. You’d then need an xchat-perl package, an xchat-tcl one, an xchat-gtk , . All these packages need to be maintained, patched, upgraded, etc. That’s a lot of work.

The second option gives you a bloated XChat package that pulls in lots of other stuff, most of which won’t be used at all by the average user. Not really satisfactory for distributions like Arch.

You can try to find a sweet spot between these two, but chances are you won’t find the perfect fit.

What the Arch devs apparently did with the package is ship a commonly used plugin without forcing the user to install the dependency. That (leaving out the error message for now) is actually pretty nice for the user: those who don’t want/need the TCL don’t have to install it to get XChat. Those who do can just install TCL and the XChat TCL plugin will just work.
So that’s a nice compromise. If you, in the future, would like to use TCL to script your XChat, all you’ll have to do is install TCL — you won’t have to worry about updating XChat or installing yet another package.

As for the error message, it’s purely cosmetic. Could it be fixed? Probably.
Could it be fixed easily in a way that still lets the plugin start working right after installing TCL (without additional packages or configuration changes, reverse dependency checks, . ): that’s not all that certain.
Should the Arch devs/maintainers spend time on trying to remove this cosmetic issue? That’s debatable. Giving that the software works, this should be pretty low priority.

Could you try and fix it one way or another? If it’s important enough for you, probably. Give it a shot: find a better way of handling those plugins and dependencies, and file a bug or feature request, or get on the appropriate forum/mailing list for this type of thing.
Open source distros don’t get better by magic. If you care enough about this, get involved.

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