DevOps Day-8 Basic Linux Shell Scripting for DevOps Engineers
The challenge is for the DevOps Community to get stronger in DevOps
I am a highly skilled QA and testing manager with over 19 years of experience in the industry. I am passionate about ensuring the delivery of high-quality software and have a proven track record of successful project delivery. Additionally, I have extensive experience as a DevOps engineer, which has given me a deep understanding of the software development lifecycle and the importance of collaboration between teams. I am committed to staying up-to-date with the latest technologies and methodologies in the industry and am always seeking new challenges to enhance my skills.
Welcome to Day 8 of our Basic Linux Shell Scripting for DevOps Engineers! In today's session, we will cover the following topics:
- Input and output redirection: Input and output redirection are used to redirect the standard input, standard output, and standard error streams of a command. The most commonly used operators for input and output redirection are "<", ">", and ">>".
- "<" operator: The "<" operator is used to redirect the standard input stream of a command from a file. For example, the following command will read the contents of the file "input.txt" and pass it as the standard input stream to the "grep" command:
graphqlCopy codegrep "pattern" < input.txt
- ">" operator: The ">" operator is used to redirect the standard output stream of a command to a file. If the file already exists, its contents will be overwritten. For example, the following command will write the output of the "ls" command to the file "output.txt":
bashCopy codels > output.txt
- ">>" operator: The ">>" operator is used to append the standard output stream of a command to the end of a file. If the file does not exist, it will be created. For example, the following command will append the output of the "ls" command to the file "output.txt":
bashCopy codels >> output.txt
- Pipes: Pipes are used to connect the standard output stream of one command to the standard input stream of another command. The "|" symbol is used to create a pipe. For example, the following command will list the files in the current directory and then filter the results to show only the files that contain the string "test":
bashCopy codels | grep "test"
- Command substitution: Command substitution is used to replace the output of a command with its result. The most commonly used syntax for command substitution is "$(command)". For example, the following command will list the files in the current directory and then count the number of lines in the output:
bashCopy codeecho "There are $(ls | wc -l) files in the current directory"
These are some additional concepts used in shell scripting. By mastering these concepts, you will be able to create more complex and sophisticated scripts. Keep practicing and experimenting with shell scripting, and you'll become a proficient DevOps engineer in no time!
