I'am learning about embedded systems, and i was able to compile and setup a SAM9x35 EK with buildroot, mounting the bootstrap, the U-Boot, the Linux and The rootfs (Buildroot's basic RFS[root file system]skeleton).
I have LOTS of questions, but one of the most important is:
Pre Question Statements, for context:
I already have a provided JFFS2 with and app inside that is made of several NetBeans (c++) projects.
These projects use kernel built in (if selected in buildroot's menu) libraries
How does it work?
How the rootfs and the netbeans (makefiles) connect to linux packages?
What I mean is, How the kernel manages the makefiles from the netbeans projects?
i.e.: If i create a project that shows a picture on the screen i add some needed packages to the rootfs and then this is flashed to the device. How the kernel knows how to read and run this app? What I have read after doing this question is that Kernel start some script in init.d folder. But I would like a more Conceptual explanation of the interaction between Kernel and Rootfs
Any Explanation could help me because i dont understand how exactly works. The application is a standalone application that is loaded at the start of the linux (power on) and is only that, it runs and uses hardware to go through its different functions.
Please feel free to use links or examples.
Thank you very Much.
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Hi i have an application written in GTK and i would like to make it into an bootable ISO file.
I have tried many options but have failed and being sent in many directions using cmake and make by following several tutorials which did not work.
Does anybody know how to create an bootable ISO file for / from an GTK based application on linux / ubuntu?
I am currently using ubuntu to develop the bootloading application yet i would prefer the GTK application to startup when the computer starts up, and have no operating system running if possible?
GTK requires an operating system kernel (a Linux kernel...) to be running, and some display server, e.g. Xorg.
So you need to actually make your custom Linux distribution.
I would prefer the GTK application to startup when the computer starts up, and have no operating system running
This is not possible
But you could study the source code of source based Linux distributions like Gentoo and work for several months to make your own Linux distribution.
You probably would need help and address many issues you did not even thought of (e.g. AZERTY keyboard layout, computers with only USB disks, laptops with only Wifi network connections, etc...)
Notice that Debian & Ubuntu can be configured to boot some (open source) GTK based installation procedure. I guess you could study in details their implementation (since it is open source)
It's not possible to boot a GTK application without operating system, as Basile Starynkevitch said.
However, you can use Linux to display only your GTK distribution, without any additional programs and I think it can be done easier, than Starynkevitch's method.
You can try to use the tool Systemback or similar to create a bootable live Linux distribution. Systemback is not maintained anymore but there is a github fork made by BluewhaleRobot that appears to be more up-to-date.
You can install a light Linux distribution, for example Xubuntu, and remove all unnecessary packages and programs. You can set the wallpaper, remove or leave the taskbar/menu start etc. Then, install your GTK application, add it to autorun and use Systemback's "Live system create" function.
The ISO image should be created and your program should be already installed in it with autorun.
It's not a perfect and stable solution, however, it seems to be the easiest way to achieve what you want.
I want to build a minimum Linux for embedded devices that comes with Firefox only.
Questions:
Is it ever possible to add X11 components to runlevel3 and
upgrade it to runlevel5?
Is it possible to setup a Linux in runlevel3 with minimum display support so that I be able to run
Firefox? (Not interested in text based browsers)
I gave it a go but I got lots of dependency errors trying to install X11-common with apt-get in runlevel3.
Linux From Scratch is a step-by-step instruction book for anyone who wants to gain a good understanding of how to build own custom Linux distro.
There is a dedicated topic about X Window System Environment
This includes the base LFS project and a bunch of extensions derived from it. For embedded systems Cross Linux From Scratch is of particular interest.
Another option - in case you want to do it faster but losing deep understanding - is using some Embedded Linux distro builder like Buildroot
I may have a couple assumptions of Linux incorrect about the Linux system, and for that I apologize.
I have been educating myself on the Android and Linux systems for a while now and I started looking into installing a custom boot loader and Linux system onto an older Samsung tablet. Immediately upon looking into the feasibility of this, most of the answers I could find were that it wasn't possible because you would need the drivers that are being used by the android kernel to communicate with the OEM hardware in whatever Linux kernel you are installing.
I have one of these tablets rooted and I believe I may have found the drivers I need (not sure on that yet), and so I guess my question is, is it possible to take the drivers and put them into a Linux kernel within a distribution install image and install Linux on the device (using also a custom boot loader)?
I presume because someone hasn't done this before there is a pretty good reason why, but I am basically looking to be able to use Linux on my old tablet without the resources being taken from Android, and personally in my opinion, if I don't need Android and can install Linux straight on to the machine, then why keep it?
In the long run I am looking into LFS to create a custom distribution that can be installed on these tablets, but the most important question to me right now is if I do create this distribution can I get the drivers that the hardware needs (and even then will my kernel be able to use them?).
I also understand that some of these drivers may be proprietary drivers provided by the manufacturer, but I am not looking to profit off of this but instead research the feasibility of a better personal on-the-go computing setup.
I may be terribly wrong on how I may have described some things, so here are some of my assumptions:
The .ko files in the Android /lib/modules/ directory are the static kernel drivers I am looking for for that device.
The drivers aren't written for specifically the Android system, but for all Linux variants and would be compatible with another distribution.
If the drivers were written for the Android system, then one would be able to edit or modify those drivers to work with a different distribution.
One could "put the drivers into an installation image", or if not, then one would have to compile the kernel from source with those static drivers.
TL:DR, If this all just amounts to rambling, here are my specific questions:
Is it possible to copy the static kernel drivers of a rooted Android device to something like the SDcard?
Is it then possible to "put" or "compile" those same static drivers into a Linux distribution before installing it onto said tablet using something like Odin, or the like?
I'm working on a side project which requires me to configure and compile a tiny Linux System based on Ubuntu.
The result should be a tiny OS with the following features:
A Bootloader
A Kernel
A Process
A Thread
Miscellaneous (if possible)
A File System
Virtual memory
A Console
I read lots of documents about it, one of them being: http://users.cecs.anu.edu.au/~okeefe/p2b/buildMin/buildMin.html#toc3
I deleted the file system, and recompiled the kernel using make xconfig. I tried to deactivate modules and configurations many times, but it's not working for me.
How can I configure the kernel for the OS with only the features I listed above? What options can I disable or enable while still having a working system?
Having the Kernel very small is not important for Ubuntu, so maybe choosing Ubuntu is part of your problem. I would use as starting point what OpenWRT does. They do a good work making the Kernel small and it is easy to get started. OpenWrt Buildroot – Usage
try Linux From Scratch. It is a step by step approach on building a minimal Linux system from which you can evolve later on. http://www.linuxfromscratch.org/.
Use Gentoo Linux distribution - it's great for practicing on creation of Linux systems. Gentoo has excellent setup documentation, for example about configuring the kernel.
And Gentoo is a little easier and faster to setup than Linux From Scratch (LFS). If you want to go deeper, then LFS may be a good learning step too.
I know about several projects for cross compiling between linux and Windows.
The Wine project is great for running windows application inside Linux.
andLinux is a linux running inside Windows.
My question is, can we compile a complete linux OS with a Windows compiler (like mingw32, visual studio , ...) in order to get a linux system which is fully compatible with the Windows PE executable format ?
As wine demonstrates, the PE format isn't really the problem with compatibility.
PE only defines how the program is pieced together at load time. Under windows, RUNDLL interprets it, loads all the program sections to memory, loads all the supporting dlls to memory and patches up the function pointers so that there is a program sitting in memory ready to go. (See http://msdn.microsoft.com/en-us/library/ms809762.aspx for more details. Its a good read!)
There is little stopping you writing a kernel module to do all of this. With the details in the page linked above it may not be to hard and someone may already have done it.
The real issue is the fundamentals of the operating system. Even if linux could load a PE, there would be problems around the fundamental difference in file names (\ or /) as well as the permissions model which is different and the windows registry which doesn't exist under linux. That's before you get into the different windowing model for GUIs.
Therefore the task of getting a windows program to run under linux is less about the program loader and much more about emulating all of the windows DLLs under Linux. As i understand it, this is the main heart of wine.