Display Managers
 

Somebody enlighten me about Display Managers pls. I have Slackware-15.0 with XFCE. I don't have any kde packages installed.

/etc/rc.d/rc.4 makes 2 attempts to start gdm before anything else, although AFAIK, it doesn't exist on the dvd as it's a part of gnome. Then it tries for sddm, which appears last in a 32bit version for 14.2. It doesn't exist either, of course.

Lastly, it has comments to the effect that if we've no decent DMs, we'll have to suck it up and use xdm. Unusually, Slackware only supplies xdm, so X starts.

So:

• What's so bad about xdm?
• Is lightdm (Which slarm64 uses on my RazPi 4) any better?
• Is it a good idea to run kdm (which slackware presumably supplies) for xfce and how much else of kde does kdm need?

In a perfect world, everyone does a full install and ends up on sddm (which, along with xdm is the only one provided by Slackware, but is started up earlier in the rc.4 script) regardless of the WM or DE used.

And everything works as it should

But, if you haven't installed kde/, you will land on xdm
Another possibility is to use a 3rd party DM like lightDM (provided by Monsieur Spaier for example)
https://slackware.uk/slint/x86_64/slint-15.0/source/
and lightDM & lighDM-*

Side note: As long as xdm is supplied by Mr. Volkerding, we can consider it safe & effective

sddm = kdm with the Plasma 5 transition.

If you want to try be aware that:

1. You will also need lightdm-greeter-gtk and preferably lightdm-gtk-greeter-settings
2. To build these packages you will need also the package slkbuild as for these I wrote SLKBUILDs, not SlackBuils as build scripts.
3. If you are confident enough, you can save you some hassle installing pre-built packages available in https://slackware.uk/slint/x86_64/slint-15.0/slint/ Caveat: they work on Slackware 15.0, probably not in -current.

The SDDM is a Qt5 only application and it can be installed without the other packages from /kde series.

Kdm is from KDE4 and is not modularized as Sddm from KDE5 is. It comes with kde-workspace from KDE4 which is the whole core of Kde4.

Another simple DM is gdm from GNOME 2 which has few dependencies : libart_lgpl and libgnomecanvas.

I mentioned them:
Right, I should have quoted the binaries instead of the sources
And, it works well in -current, at least the last time I tested it :-)

and also libcroco, but I agree: I ceased to ship it in Slint-15.0 because of security concerns (it hasn't been maintained for ages) but I regret it: more features than any other, and also fully accessible with speech.

I use xdm. It's quick and pretty hassle-free. For frills, try Alien Bob's (Eric Hamleer) iteration of xdm included on his Live iso's (and available on SBo as xdm-slackware-theme) or slackware-xdm-theme also at SBo.

Xdm works fine, but lacks som nice features like a menu to choose desktop environment. Instead the choice of desktop environment has to be hardcoded in a file in each users home directory unless they want the system default desktop environment.

If I remember right xdm also lacks support for starting multiple sessions for different users on the same machine on different virtual consoles. This is a functionality that is initialized by the screen saver, when you come to a screen that has been locked by another user you get the choice to start a new session and will get something like display :1 reachable by ctrl-alt-f8. The previous user can get back to his/her session by pressing ctrl-alt-f7.

As SDDM did not cut the mustard I evaluated a number of different login managers, but lightdm did not meet all my requirements. If I remember right it could not present a list of selected users only for a system getting its users from a NIS server.

I ended up installing the base core of TDM (Trinity Desktop Environment) just to be able to run tdm which behaves like good old kdm.

SDDM would give the user a menu to choose desktop environment, but that was about the only good thing with SDDM. It failed presenting selected users from a NIS server, it did not support XDMCP and it seemed to be in some buggy pre-beta status.

regards Henrik

I use xdm mainly because it does not undo any changes I make via xrandr. If using an external monitor, I manually use xrandr to enable the monitor and disable the laptop screen. If I exit out, sddm resets to use both monitors. (I like using only 1 monitor at a time).

But seems after a while, I loose just the F-Keys while in a window manager started via xdm, sddm no issues (in the past it was all keys via xdm). I had found a workaround, but seems after some past upgrade that workaround stopped working. I have been trying to find another method but it is slow going.

Seems only with fluxbox the issue does not occur (something new). It happens with fvwm2&3, twm, mwm and a few others. It happens with and without using an external monitor.

Will update the blog if I find a 'fix".

In an ideal world, it's runlevel 3.

Well, thank you all for the detailed and informative replies. I have all the information I want, with more than a little left over. Accordingly, marking this solved.

So, xdm isn't that bad, sddm isn't that good (Not that I'll ever set up NIS here!), kdm has lots of dependencies, and gdm is either perfect or needs maintaining. So, if I do nothing, I'm OK.

That part isn't entirely true. There's certainly no on screen menu and its a bit of a hidden feature, but you can configure xdm to choose different sessions based on a keypress at login time. I've been using that for many years here.

The XDM config and companion Xsession script as shipped in slackware are pretty horrid. One can make it much nicer.

You can add more X sessions in /etc/X11/xdm/Xservers. Additional sessions start on next available virtual console. I usually have X on :0 and Xvnc on :1