Running a program in linux (debian) on startup - linux

I would like to point out that I tried A LOT of different tutorials from the internet but they don't seem to work...
Adding stuff to init.d, rc.local etc. for some reason it doesn't work.
I'm really desperate to get this done, but I'm a total noob when it comes to linux.
when I type in "matchbox-keyboard" it runs just fine and as intended.
That's literally all I want, but I'd like to run it every time so when I turn my raspberry pi on, I won't have to connect a keyboard and a mouse to initialize on-screen keyboard.
Is there a simple way to get this done, something like dropping the program into autostart folder in windows?
I have no experience with linux at all, I don't know how to write scrips and all that stuff and all I want is to run this "matchbox-keyboard" after every reboot...
Please help me, I'm really desperate and I can't figure it out. Spent all day doing it and still nothing...

The simplest way is to drop in a new cronjob (a cronjob is a task that is scheduled to run at a particular time):
crontab -e
This allows you to edit your cron file. Instead of putting in a time, use #reboot. So you should have a new line in your cronjob file that looks like this:
#reboot matchbox-keyboard
The cronjobs run in a different environment from your login environment, so you may need to use the full path to the program. I'm also not familiar with the matchbox-keyboard program, but it looks like it will run fine since it can run as a background process.

Maybe you have gnome-tweaks installed?
apt list gnome-tweaks
Listing... Done
gnome-tweaks/stable,now 3.30.2-1 all [installed,automatic]
It has a graphical Startup Applications function that allows you to select application icons and start them at LOGIN time. I use it to start my favorite text editor.
Starting things like an Apache server (e.g. XAMPP) at BOOT time is a whole new ball game. I used this link as a starting point.

Related

Autostart GUI application with LXDE session

There's quite a bit of information out there on this topic, but for some reason I just can't get it to work. This is on a raspberry pi running the 'DietPi' flavor over the raspian distro, and is perhaps what separates my question from the others.
So I have a GUI application that I wish to launch at boot, after the LXDE session has begun. So I have utilized the following file here:
/etc/xdg/lxsession/LXDE/autostart
and added the line:
#/myapplication
This works, however, it launches multiple instances of this program, and the first one always crashes. This creates problems because there's some competition for resources (IO, files, etc). So what I did was create script file, /myapplication-autostart.sh instead like so:
if pgrep "myapplication" > /dev/null
then
echo "my application is already running"
else
/myapplication
fi
and then changed /etc/xdg/lxsession/LXDE/autostart to #/myapplication-autostart.sh. Now what I find is the program launches once, but the instance crashes. It crashes when it attempts to create a window (opencv imshow). This is strange because the program will also run headless if an X-session is not available, but for some reason it crashes and I do not know where to check why.
Also, to test it wasn't an issue with the script file, I commented everything out except the /myapplication and I have found the script file runs in a continuous loop and every time I close the application it opens back up. I'm not sure why this is either.
I've tried adding a sleep delay in the script and it does not help. For whatever reason, it seems the LXDE autostart script is ran at least 3 times when booting the pi and the circumstances around the first cause the program to crash. Does anybody understand this sequence and behavior of calling this autostart script?
It is also possible to use the XDG standard Autostart - which is independent of the used desktop environment - by placing desktop files at
$XDG_CONFIG_HOME/autostart (by default ~/.config/autostart)
or for system-wide autostarts at $XDG_CONFIG_DIRS/autostart (by default /etc/xdg/autostart).
Such a .desktop-file could look like:
[Desktop Entry]
Type=Application
Version=1.0
Name=JDownloader
Exec=/usr/local/bin/my-application.sh
Categories=Utilities
The specification of desktop-files can be found at freedesktop.org.
Here was the final solution...
/etc/xdg/lxsession/LXDE/autostart added the line:
/myapplication-autostart.sh
and /myapplication-autostart.sh was changed to:
#!/bin/bash
if pgrep "myapplication" > /dev/null
then
echo "my application is already running"
else
if [[ "$DISPLAY" = ":0" ]]
then
/myapplication
fi
fi
I had to write the display variable to file in combination with the errors to file to discover the issue. At login 2 X sessions were created, display ":1" and display ":0", in that sequence. Display ":1" crashed because, although not headless, it was not initialized to a particular resolution and there was some resizing code in my program. Display ":0" was the actual display on the HDMI out and the one I wanted. Really, the conditional check to see if the application isn't necessary but I left it in there to be safe. I could have also left the # on the LXDE autostart file but it got annoying in the cases I wanted to close the application because it'd keep re-opening. Possibly I'll put it back later.
Thanks for the help!
First, some comments about opening several instances of the program: when you use "#" at the beginning of the line on the startup file (ex.: #/myapplication), this requests your system to try to launch the program, but if the program fails to open correctly, then the system will try to open it multiple times until it opens correctly -- if you remove "#" from the line beginning, then the system will only try to open the program once.
Now, to find out why the program is failing, I advise you to add
2> /file/log
to the end of every command on your script. Doing so would append any error message to a log (/file/log), and analyzing those error messages would be key to find out why the program is misbehaving.
One important note: if your program needs root privileges to run, then it will fail when called via /etc/xdg/lxsession/LXDE/autostart, as this method calls programs without elevated permissions.
This is an old thread but I was having problems getting autostart to start all the tasks listed. After many days I concluded there were one or more "invisible" characters that autostart didn't like. So I deleted the lines for the tasks that didn't start and retyped them. That solved the problem!
I think I corrupted the lines because I was editing some of the lines on my Windows computer. It was likely inserting CR with LF or some other stuff. I WILL NEVER EDIT TEXT FOR LINUX USING WINDOWS!
Maybe someone else will hit this problem and this may help them. I don't know where else to put this information.

How to reenter Linux process after closing putty

I'm new to Linux.Yesterday I wrote some Python codes,now I'm using Linux to execute my codes,it may take a few hours. As my Linux is not native,it's a remote server,I use putty to connect to it.
Now ,I want to close putty and go to sleep.But I don't know how to find my process again and reenter it after I wake up and start putty.And also,I wrote some code to print progress rate,next time when I find the process,can I see the print info again?
Run screen, start your programm and close the connection. After logging in again, use screen -r to resume your session.
Alternatively nohup will do the trick.
screen is the best built-in tool that's always available for that, although it gets a bit weird around keyboard shortcuts, some of which sometimes don't work the way you want exactly.
I've found tmux to be much better in terms of usability.
Alternatively. take a look at mosh, which is trying to replace ssh. It's a mobile shell tool from MIT that supports intermittent connectivity, lots of praise there.

Terminal not clearing after auto start bashscript in raspbian wheezy

I'm using a raspberry pi 2 to show all the video's in a folder. The raspberry automatically boots up (with a generic electric timer) in to console (not the gui) and after it boots it runs a bashscript I found here. This bashscript contains an infinite loop to play all the videos in a folder using omxplayer.
When I boot in to consolemode and manually start the script everything works perfectly. The terminal screen clears, the first video starts, and after it ends there is a second or two of black screen (empty terminal) and the second video starts playing. This is exactly what I want.
However, when I use crontab to start this script (#reboot /path/to/script.sh) the terminal messages stay and it doesn't clear everything between video's.
I've tried creating my own script that first clears everything, and then calls the second script. But this doesn't work.
I'm really really new in this field (but I'm having fun) so any pointers in the right direction would be appreciated!
P.S. I edited the /boot/cmdline.txt file so it doesn't display critical kernal logs as a work-around.
You should not be doing this using cron. You should be changing the inittab so that it runs outside any environment that may be created. See the inittab(5) man page for details. You may also be interested in openvt(1) as well.

Duplicate keyboard typing to another terminal

I have laptop-desktop setup at home and I have successfully cloned my Archlinux installation from one to another. However, I would like to avoid having to {install all new software, edit settings, update} twice, so I was wondering if it'd be possible to log over ssh from laptop to desktop, do something in terminal and have linux copy everything I type into second terminal with ssh logged in?
Thanks for ideas!
You could type the commands into one terminal then edit ~/.bash_history and save the commands into a script. Copy the script onto the machine with the second terminal and execute it. The advantage of this is now you have a script that saved your setup so you can reuse it whenever you need to.
You can use clusterssh, which duplicates your typed input across multiple systems. It is designed for situations in which the exact same tasks, such as software installation or configuration commands, are needed to be performed exactly the same on multiple systems. See http://sourceforge.net/projects/clusterssh/. Also, the KDE Konsole terminal has similar functionality.

Tutorial/Guide to create a classic, small Linux application in a package (Debian)

I've made a small script in my machine, and an alias in .bashrc that calls it. It's a bash script with 3 lines, but it can grow.
Now, some people in my team found it useful, and want to use it.
Instead of saying "copy this alias, do this, do that, install that lib" I was thinking about creating a simple package to be a little more professional. Fact is, I've never done something like this before. And the problem to me is not creating a package, is trying to decide what usually do you put in a package.
Suppose I want to take my script, and create myapplication. I want to create a .deb file that my team would install and:
Have a /usr/bin/myapplication or /usr/sbin/myapplication (what's the difference between them?), so they would just call myapplication at their terminal and it would work;
Have a man page; (Where are usually located man pages in a debian system?);
Have a possibility to read a .myapplicationrc in home folder with some configurations;
Have an entry for shortcuts in a gnome installation (is it possible to have an universal shortcut "format" that's is available to KDE and Gnome as well?);
Install dependencies.
I'm new to all that stuff. I usually code simple scripts and create an alias in my bashrc. I've never done a package before. Which guides do you know of that can help me accomplish what I thinking of above?
Here is a place to start, though I welcome a more succinct answer.
I couldn't find a complete guide. I think the best thing to do is download a package that does exactly what I'm thinking of and do some reading, like taskwarrior.

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