Changing the default directory for compiled binaries

[frozenpenguin]

I am trying to emerge a package and want the emerged package to be stored on a USB. However, I do not know which variable to change in portage to make portage behave as I wish. I also do not know how to let the terminal know the commands associated with the package if the package isn't in the default package directory. Any assistance will be appreciated.

[Josef.95]

The variable for this is PKGDIR
this is documented in "man make.conf"

[frozenpenguin]

From what I understand, PKGDIR is where binary packages downloaded off the internet are stored. I am trying to find the default directory where the packages compiled from source on my machine are stored.

[flexibeast]

The variables used during the build-and-merge process are documented in ebuild(5) man page and in the devguide. There's also the ebuild(1) man page which describes the various phases involved.

Depending on exactly what you want on the USB drive (a single binary package? a directory-and-file-tree, given that a single package might install more than one binary, and possibly various libraries and other supporting files as well?), emerge(1)'s `--buildpkg*` options, and the the quickpkg(1) program, might be relevant.

If none of the above helps, please provide more information about exactly what you require.

[Hu]

[frozenpenguin]

My idea is to install a package on a USB. When the USB is mounted, the system should treat packages installed on the USB as if the packages were installed on the system's partition. Only the packages binaries and dependencies which are required by those but not by any packages on the system should be installed there, as I do not want packages I periodically use installed on my computer as I wish to prevent storage issues on my system before they arise.

[eschwartz]

[Hu]

frozenpenguin: what are the specifications for the system where you want to do this? How much storage do you think you need for these programs you intend to relocate to USB? I concur with eschwartz that at this stage, it looks like you are trying to avoid a problem that may never come to pass, and are definitely setting yourself up for additional hassle in the attempt.

[pingtoo]

[pjp]

Isn't using the USB simply a sneakernet method?

Am I missing something? Why would that be meaningfully different than downloading them from a network connection?
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Quis separabit? Quo animo?

[Hu]

As I understand the thread, OP is not merely using a USB disk as an alternative to downloading the source files over an Ethernet/Wifi connection. OP wants to use the USB as a conditionally present seamlessly available filesystem hosting finished runnable programs. For example, with USB absent, the system can only run a lightweight desktop, like Xfce4. Plug in the USB, and suddenly you can also choose GNOME or KDE Plasma as desktop options.

[frozenpenguin]

My current setup on my computer is around 85GB for linux and around 383GB for windows. Now, I could add more space for linux except windows isn't willing to give any more space up from its partition using its disk management tool. I also don't want to delete windows as I may need it again in the future.
As I only want to install packages I rarely use, packages on the USB will only be updated when their use is required. The reason these packages are rarely used is because I never use these packages unless it is required for certain features(such as some sites requiring use of a certain browsers for certain functionality).

[e8root]

To allow reducing size of Win10/11 install you need to disable pagefile and hibernation, restart and then defragment your drive.
I would also recommend using folder compression on programs and files you don't really use all that often. Of course already compressed files do not gain much from compressing them again but on average gain can be quite good for typical programs. Most gains are on things like large number of small text files.

As for what you want to achieve in OP I am not sure how to achieve it, or at least in automated way as manually you could probably move some files and perhaps use LD_LIBRARY_PATH to move some .so files to other locations. Doing it manually can quickly lead to issues if you don't know exact dependencies. Automating this... should be doable but sounds like a lot of effort hacking Portage.

Probably (very...) better solution would be to use something like Flatpak or Appimage packages. Especially the latter one you should be able to just put on USB and run as portable programs. Flatpaks I am not sure but should be doable. There are also Snap packages but we neither use nor talk about Snap packages ; ) But seriously it seems you need SystemD which you might have or not and I personally am lest interrested in these even if I myself do use SystemD.

There are also other more source-based solutions like Nix and Guix package managers. The latter one is not free to use anything not free so might not have all programs you would want. Both work in similar way and allow you to build your packages. By the the looks of it it should be possible to achieve having Nix/Guix programs in separate mounted directory without needing anything on your base system. Downside it you would then need to learn new build system and there is some disk space overhead as you will need all the build tools like compilers.

Lastly it is possible to chroot in to existing Linux install and run applications from that. It can be Gentoo and in this case its like separate Gentoo environment which can be system which might not even be bootable/usable standalone but could easily be made as standalone bootable system or some other distro. It requires some tinkering if you want to run GUI apps or whole X11/Wayland servers but it is doable. It is of course abusing chroot and issues are expected, especially if you run something like Ubuntu. There for example Snaps don't work and cannot be made to work. Otherwise Especially for Gentoo itself it might be a good idea to have such system as it can be useful for testing, troubleshooting and such.

Then there are other solutions like LXC or docker.
Depending on your specific needs and compatibility either of those or others which I mentioned and didn't mention can be usable.

Most sane and "just works" solution is however something like Appimage.
Maybe create Appimage using Gentoo? Download program you need from trusted source and just run it? Lots of different ways to do it...
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Unix Wars - Episode V: AT&T Strikes Back

[Genone]

I'd first check why you even need more than 50 GB for your linux install. Most packages only need a couple megabytes at most, so redirecting them to a USB drive wouldn't really help with space issues in the first place.
Try running

[logrusx]

[Zucca]

I'd like to add to @Genone's comment that if you want to find "where all the stuff is" then try sys-fs/ncdu.
_________________
..: Zucca :..
Gentoo IRC channels reside on Libera.Chat.
--

[NeddySeagoon]

Put distfiles, packages and /usr/src onto USB.
They are only needed at update time.
Optionally, ./repos can go to USB too.
If you must have ::gentoo available all the time, use a squashfs snapshot to save space.

Everything to run Gentoo in always available. The bits required for maintenance can be unplugged when not needed.
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Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

[Genone]

[frozenpenguin]

So I got the source files on my flash drive, however when I try to install the package I get this:

[pingtoo]

[Genone]

[frozenpenguin]

[Hu]

You originally asked to use a USB drive. I, and likely others, took this to mean a removable block storage device backed by either an SSD or a mechanical drive, not a USB flash stick. Regardless, I (and, again, likely others) assumed you would use a proper POSIX filesystem on this storage device. Whether you try to store distfiles or a compiled package on the external device, you will cause yourself considerable extra hassle if you use a filesystem that cannot represent standard POSIX features. ExFAT and NTFS are the most well known unsuitable filesystems, but there might be others.

As I wrote at the start of the thread, there is no generalized mechanism to change the prefix for individual packages to be other than the Portage default. The Gentoo Prefix project can relocate the entire resulting Gentoo system under a prefix, but that's not what you requested.

The general advice for dealing with systems that have limited internal storage is to use existing functionality to trim down which files the package installs, such as by eliminating unnecessary translations, stripping debug symbols, discarding documentation, and so on. If storage is very limited, use ROOT to install a non-self-sufficient system. Excluding compilation tools can save you substantial space.

[Genone]