If you run the find command as a non-privileged user, you may see “Permission denied” messages for certain directories or files that you don’t have permission to access. To avoid these messages, you can use the 2>/dev/null redirection to discard the error output from the find command. For example: find / -name “example.txt” 2>/dev/null This … Read more

You can use the man command to read a man page from a local directory in Linux or Unix. By default, the man command searches for man pages in the system-wide man page directories. To read a man page from a local directory, you need to specify the path to the man page file using … Read more

Bash completion is a feature in the bash shell that allows you to auto-complete commands, file names, and other things by pressing the Tab key. To install and activate bash completion in RHEL/CentOS Linux, follow these steps: Install the bash-completion package: sudo yum install bash-completion Add the following line to your ~/.bashrc file: if [ … Read more

You can use the dpkg command to see what packages are installed on Ubuntu Linux. The following command will list all installed packages: dpkg –list This will display a list of all packages installed on the system, including their names, versions, and descriptions. Another way to see installed packages is to use the apt command: … Read more

In FreeBSD, you can use the acpiconf command to find out the battery life status of a laptop. To get the battery status, run the following command in the terminal: acpiconf -i 0 This will display information about the first (0th) battery in the system, including its current charge level and whether it is charging … Read more

Python has a built-in module called argparse which makes it easy to write user-friendly command-line interfaces. The following are some examples of using argparse to handle command-line arguments: import argparse parser = argparse.ArgumentParser(description=’Process some integers.’) parser.add_argument(‘integers’, metavar=’N’, type=int, nargs=’+’, help=’an integer for the accumulator’) parser.add_argument(‘–sum’, dest=’accumulate’, action=’store_const’, const=sum, default=max, help=’sum the integers (default: find the … Read more

This error message usually indicates that the required header file, “gnu/stubs-32.h”, is missing from your system. This header file is part of the glibc library and provides stub definitions for 32-bit system calls on 64-bit systems. To resolve this issue, you can try installing the glibc-devel package for your Linux distribution, which should include the … Read more

The “start” command in Linux can be used to run a command in the background. When a command is run in the background, it executes as a separate process in the system and does not block the terminal. To run a command in the background, you can add an ampersand symbol (&) at the end … Read more

To add line numbers to a file in Linux/Unix, you can use the nl command. Here is an example: nl file.txt > numbered_file.txt This will create a new file numbered_file.txt with line numbers added to the contents of file.txt. The nl command can also be used with other options and arguments to customize the line … Read more

To install sudo on a FreeBSD system, follow these steps: Run the following command as the root user to update the package database: # pkg update Install the sudo package: # pkg install sudo To configure sudo, you will need to edit the /usr/local/etc/sudoers file. Use the visudo command to edit this file: # visudo … Read more