In this example, the script checks the user’s input against three patterns: ‘apple’, ‘banana’, and ‘cherry’. If the user enters ‘banana’, the script prints ‘You entered banana’. If the user enters so
The script takes any temperature as an argument and then displays a message that reflects what would the weather be like. If the temperature is greater than five, then the nested (inner) if-elif statement is evaluated. Let’s do a few runs of the script to see how it works: kabary@han...
Pay special attention to space. There must be space between the opening and closing brackets and the conditions. Similarly, space must be before and after the conditional operators (-le, == etc). Here's what it shows when I run the script: Did you notice that the script tells you when ...
Conditional operators such as‘-f’ must be unquoted to be recognized as primaries. When used with [[, the ‘<’ and‘>’ operators sort lexicographically using the current locale. When the ‘==’ and‘!=’ operators are used, the string to the right of the operator is considered a pat...
Modifying strings with pattern matching substitution Modifying strings with tr, awk and sed 10-minute break Segment 5: Using conditional structures Length: 50 minutes Using if then else Using logical operators && and || Using while and until Using for and case. Q&A Length: 10 minutes ...
Loops and conditional statements are also popular in bash scripting. We’ll look at a few instances of using both in the same script:#!/bin/bashisvalid=truecount=1while [ $isvalid ]doecho $countif [ $count -eq 5 ];thenbreakfi((count++))done...
3. UseCtrl-oto save the file, thenCtrl-xto exit. Then,run the scriptby entering: bash bashtest.shCopy Using Code Snippets to Check for Multiple Files It is also possible to check if multiple files exist using theif conditional statements. Follow the steps below to create a script and ve...
if statements in bash script use square brackets for the logical condition and also have support for else and elif (else if) branches. Bash supports standard programming language conditional operators such as equals (==), not equals (!=), less than and greater than (<, >), and a number...
A Shell script usually needs to test if a command succeeds or a condition is met. In Bash, this test can be done with a Bash if statement. As with any other programming language, Bash comes with conditional expressions that allow you to test for conditions and alter the control flow if ...
Bash Script File </> Copy #!/bin/bash num=50 if [ $((num % 2)) == 0 ] || [ $((num % 5)) == 0 ]; then echo "$num is even or divisible by 5." fi Output 50 is even or divisible by 5. Bash OR Operator in While Loop Expression ...