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How does if work in bash?
The if statement starts with the if keyword followed by the conditional expression and the then keyword. The statement ends with the fi keyword. If the TEST-COMMAND evaluates to True , the STATEMENTS gets executed. If TEST-COMMAND returns False , nothing happens, the STATEMENTS gets ignored.
How do you end an if statement in shell script?
2 Answers. Try replacing the last line ( endif ) with fi , which is the correct token to close an if statement. Also, replace ($2 == “both”) with the correct [ $2 == “both” ] . Note the quotes around $2 , the spaces after [ and before ] and the ; before the then .
What does the select construct do in Bash?
The select construct allows the easy generation of menus. It has almost the same syntax as the for command: The list of words following in is expanded, generating a list of items. The set of expanded words is printed on the standard error output stream, each preceded by a number.
When to use$ ( command ) in bash script?
From the bash variables tutorial, you know that $ (command) syntax is used for command substitution and it gives you the output of the command. The condition $ (whoami) = ‘root’ will be true only if you are logged in as the root user. Don’t believe me?
How to use conditional statements in bash scripts?
In this part of the bash beginner series, you will learn how to use conditional statements in your bash scripts to make it behave differently in different scenarios and cases. This way you can build much more efficient bash scripts and you can also implement error checking in your scripts.
Are there test conditions that you can use with Bash?
There are numerous test conditions that you can use with if statements. Test conditions varies if you are working with numbers, strings, or files. Think of them as logical operators in bash. I have included some of the most popular test conditions in the table below: