Linux commands⚡

Created

Jul 1, 2023 9:04 AM

ROS Essential

Creating a Workspace

mkdir catkin_ws && cd catkin_ws

mkdir src && cd src

catkin_make

source devel/setup.bash

echo $ROS_PACKAGE_PATH  : to check correct path 
or
echo "source ~/catkin_ws/devel/setup.bash" >> ~/.bashrc

make sure to add to ~/.bashrc

Creating a package

catkin_create_pkg pkg_name std_msgs rospy roscpp

Always create the package inside the src folder.

ROS core cmds

- roscd pkg_name
- rospack find pkg_name
- rostopic list , info , -help
- rosnode list , info , -help
- rosrun rqt_graph rqt_grpgh

ROS essential commands

-rostopic info /[name of list]
-rostopic type /[module type]

-rosnode list    #to list all node running 


-rostopic eco #to read the message which is publishing from the ode
-rosmsg show [] #node name

run the main exe to list the all available topic

Raspberry Pi Essential

To create a virtual environment in python!

mkdir project-name && cd project-name

python3 -m venv oled

source oled/bin/activate
or
. oled/bin/activate

To remove existing SSH key

ssh-keygen -R [ip address]

ip address : 192.168.1.1.1

How to kill a processor

sudo kill -kill [process number]

for instance 3040 is the process number.

To list all devices

ls /dev/tty*

To Measure Temperature

vcgencmd measure_temp

‣

create a aliases!

To run a script on startup

nano ~/.bashrc

or

crontab -e
@reboot [script directory]

This is helpful in order to create a custom script like OLED status.

To watch a temperature of device

watch -n1 vcgencmd measure_temp

This is applicable for the processor too, just replace the temp with clock.

Managing files

- cd : change Directory
- mkdir : make a directory
- ls : list all items in a directory
- touch : make a txt file 
- nano : cmd line text editor
- sudo : admin privelige
- rm -rf : to delete a directory
- rm : to delete a file
- cntrl + shift + c / v : copy n paste in cmd
- ~ : used to navigate to home directory
- chmod +x : to make a file executable

common for Linux devices.