For this, we need to utilize the not operator “!” with the “if” statement in the bash script. Let’s discuss the use of the “if-not” operator in Bash programming with the help of some examples. Get started with the new Bash file creation while using the terminal shell of the ...
This script shows a simple example of anifstatement that uses anelseclause. The conditional test checks whether the customer's age is greater or equal to 21. If it is, the customer can enter the premises, and thethenclause is executed. If they're not old enough, theelseclause is execute...
-z is the second supported bash string comparison operator used to check if a string is empty or not. The -z operator functions similarly like -n operator. Below is an example: Most importantly, you should add spaces around the square brackets. If there are no spaces, bash will complain ...
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A basic if statement commands that if a particular condition is true, then only execute a given set of actions. If it is not true, then do not execute those actions. If statement is based on the following format: Syntax if[ expression ]; ...
string value more than zero length. There are many options in Bash to do this task. Using the “-n” option with the “if” statement is one of the ways to check whether a variable is non-empty or not. The uses of the “if -n” option are shown in the next part of the ...
if [ $count -eq 100 ] then echo "Count is 100" else echo "Count is not 100" fi Note:This article is part of the ongoingBash Tutorialseries. 3. Bash If..elif..else..fi If [ conditional expression1 ] then statement1 statement2 ...
if [ -e "$file_path" ]; then echo "The file exists." else echo "The file does not exist." fi In above example, we are checking whether a file “migratedb.sh” exists or not. If-elif-else Statement In bash script, if you wish to apply multiple conditions using if statement then...
!=: Not equal to -z: Empty string -n: Non-empty string 3. File and Directory Checks: -e: Exists -f: Regular file -d: Directory -r: Readable -w: Writable -x: Executable Example of using If Statement: Let’s illustrate the usage of if statements with a few examples: ...
Bash: If Bashscripts are used on the Linux operating system. These scripts carry out one or more commands. They are very powerful, however, as they support a number of features of programing languages. One of the major key words supported by Bash is the conditional statement, orifstatement;...