wait is a command that waits for the given jobs to complete and returns the exit status of the waited for command. Since the wait command affects the current shell execution environment, it is implemented as a built-in command in most shells. In this article, we’ll explore the Bash built-in wait command. Bash wait Command
Bash: Write to File
One of the most common tasks when writing Bash scripts or working on the Linux command line is reading and writing files. This article explains how to write text to a file in Bash, using the redirection operators and tee command. Writing to a File using Redirection Operators # In Bash, the redirection of output
Bash read Command
Bash ships with a number of built-in commands that you can use on the command line or in your shell scripts. In this article, we’ll explore the built-in read command. Bash read Built-in # read is a bash built-in command that reads a line from the standard input (or from the file descriptor) and split
How to Redirect stderr to stdout in Bash
Sometimes when you are redirecting the output of a command by piping to another command or to a file, you get the error messages. There are three standard I/O streams, which are used in Bash and other Linux shells when a program is executed. Below are the streams and each representing by the numberic file
Bash printf Command
The printf command have more control over the formatting of the output. It formats and prints arguments similar to the C printf() function. In this article we will see how to use printf command bash. printf Command# Bash and other shells like Zsh and Ksh have printf by default. The standalone binary /usr/bin/printf is also
Bash Select (Make Menus)
Using the select construct you can generate menus. In this guide, we will discuss about the basics of the select construct in Bash. Bash select Construct# You can generate a menu from the list of items using the select construct. Following is the syntax for the select construct and it is similar to the for
Writing Comments in Bash Scripts
It’s a best practice to make bash script in a clean and understandable way. You can make you code clean and arrange by indenting, blocks and giving related names of variables and functions. You can also improve the code readability using comments. Comments are human-readable explanation or short description. In this article we will show
How to Increment and Decrement Variable in Bash
Variable increment and decrement is fundamental arithmetic operation in bash scripting. It’s mostly used with the for, while and until loops. Increment means adding value to variable and Decrement means subtracting from numeric variable value. This article explains multiple ways to increment or decrement a variable. Use of + and – Operators# You must use
How to Check if a String Contains a Substring in Bash
While you working with string in Bash need to check whether a string contains another string. In this guide, we will show you multiple ways to check if a string contains a substring in bash scripting. Use Wildcards# It is easy to use asterisk wildcard symbols (asterisk) * to compare with the string. Wildcard is
Bash Arrays
Arrays are set of data and fundamental requirement for any programming language. We can say that it’s a variable with multiple child variables. This article shows you basics and use of arrays in Bash scripts. Bash Arrays# One dimensional array with numbered index and associative array types supported in Bash. Those are referenced using integers