newbie question about USE flags

mreff555 · 09-02-2012, 11:50 AM

I just installed gentoo for the first time and I'm a little uncertain about USE flags (yes, I'm reading the documentation now)

If I were to type something like

Code:

emerge -vp kde-meta

Are the use flags which it displays the default configuration or just a general list of options. I ask because the documentation makes it sound like these are just the available flags. the fact that some of them are preceded by a "-" makes me think otherwise.

Also, I generally run openbox. Can anyone give me some recommended use flags?

segmentation_fault · 09-02-2012, 02:32 PM

The use flags that you see on emerge --pretend output are the available flags for the specific package. If there are some flags that you want on every package that supports them, you add them in /etc/make.conf eg for a desktop you most likely want alsa usb etc.
Now for the openbox part, I have blackbox, which is similar. I don't plan on using KDE or Gnome, so I don't want their specific functionality, but I want to use GTK and Qt4, so part of my system-wide use flags is:

Code:

USE=[...]gtk qt4 -kde -gnome[...]

also my profile is set to desktop and not to kde or gnome subprofiles.
Finaly, keep in mind that you can define per-package use flags on /etc/portage/package.use
All these are my personal preferences. Yours might differ

Edit: Misread your question. The list you see from emerge are the flags that will be enabled (and disabled if prefixed with -) if you go ahead.

holdencaulfield · 09-05-2012, 12:09 AM

On Gentoo I always use equery for looking at USE flags, dependencies or whatever really. It's part of app-portage/gentoolkit. The documentation is good, (like all Gentoo docs). Some people might prefer something else, but its one of the first programs I install.

mreff555 · 09-05-2012, 07:45 AM

Thanks guys. (gtk qt -kde -gnome) makes sense. I'll try that.

ninja master · 09-25-2012, 06:40 PM

i generally leave my make.conf use flags generic!!!! and flag individual packages uses...

for /etc/make.conf

Code:

USE="mmx sse sse2"

and for /etc/portage/package.use

Code:

media-libs/mesa-8.0.3 xa
x11-libs/libdrm-2.4.33 libkms
gnome-base/gnome-menus-2.30.5 python
dev-lang/python sqlite
x11-libs/vte-0.28.2-r203:0 python
sys-libs/zlib-1.2.5.1-r2 minizip
x11-misc/xscreensaver -gnome
net-mail/gnubiff password
net-p2p/transmission -qt4
media-video/vlc projectm
dev-java/oracle-jdk-bin nsplugin
app-text/hunspell linguas_en
dev-lang/ruby threads

-gnome removes gnome support from xscreensaver....
xa python sqlite minizip password adds specific features to JUST the package.... everything else is compiled ultra lean untill i tell it to chow down on extra codes... i find the codes and names to insert into the /etc/portage/package.use from porthole....

if i require the latest version for some reason i hack up the /etc/portage/package.accept_keywords

Code:

>=www-plugins/google-talkplugin-3.5.1.0 ~amd64

and this says "greater than or equal to" package to version up to latest or not, if i require lower versions i use less than or equal to symbols....

once i figured this all out gentoo has officially became my favorite distribution.

(gtk qt -kde -gnome makes absolutely no sense, its saying use qt and gtk, but dont use kde or gnome.... -gtk -gnome qt kde would make sense)

segmentation_fault · 09-26-2012, 02:44 AM

Quote:

Originally Posted by ninja master

(gtk qt -kde -gnome makes absolutely no sense, its saying use qt and gtk, but dont use kde or gnome.... -gtk -gnome qt kde would make sense)

Say what??? How would that possibly make any sense?
kde-meta needs qt4 and gnome needs gtk. Your emerge will fail.
On the other hand, transmission can be built with qt4 support, gtk support or both, but without integration with kde or gnome.

i92guboj · 09-26-2012, 04:32 PM

Yeah, there's qt outside kde, and gtk+ outside gnome, just like there're OS's outside Windows.

Going farthest, you can perfectly get a complete kde desktop with USE="-kde" if you want. Remember: USE flags control features that are optional. If you install KDE, all you need will be pushed, it doesn't matter if you are USE'ing "-kde".

If "qt" and "kde" where equivalent, in first place, then there would be absolutely no need for two separate USE flag, would it?

mreff555 · 09-26-2012, 09:22 PM

Quote:

Originally Posted by segmentation_fault

Say what??? How would that possibly make any sense?
kde-meta needs qt4 and gnome needs gtk. Your emerge will fail.
On the other hand, transmission can be built with qt4 support, gtk support or both, but without integration with kde or gnome.

I'm using -kde -gnome qt4 gtk. I don't run kde or gnome but I still want access to all of qt and gtk's libraries.

segmentation_fault · 09-27-2012, 08:52 AM

@mreff555 my last reply was to ninja master
And it was wrong. I misread his post, I thought he wrote

Code:

-gtk gnome -qt4 kde

So, ninja master I owe you an apology. However, the other point still stands.

mreff555 · 09-27-2012, 09:45 AM

Quote:

Originally Posted by segmentation_fault

@mreff555 my last reply was to ninja master
And it was wrong. I misread his post, I thought he wrote

Code:

-gtk gnome -qt4 kde

So, ninja master I owe you an apology. However, the other point still stands.

Yes you are. Those flags would definitely cause problems.

i92guboj · 10-02-2012, 12:51 PM

If a flag combo is supposed to cause trouble, then ebuilds will usually let you know and abort the merge. Sometimes you can only enable one-of-many, and only one. Some other times selecting a flag will require you to turn one another one in the same or even in another ebuild.

If not, then it's a bug that should be reported and fixed, that's what bugs.gentoo.org is for. It's the whole point of using a metadistro. Otherwise, we would be better using LFS and solving deps by hand.

Another completely different matter is whether the flag combo will be suitable for you. But if you have doubts (or burst into shivers) about that, you should really pick one of the desktop-based profiles and don't tinker with the USE flags at all.

To sum up, there's nothing wrong about these flags, just like there's nothing wrong in using -imlib if you don't want icons in fluxbox. That's what the USE flags and Gentoo is about: customizability.