In this example, we’ve created a ‘for’ loop that acts as a ‘foreach’ loop. The loop iterates over the numbers 1 through 5, echoing each number on a new line. This is a basic way to use the ‘foreach’ loop in Bash, but there’s much more to learn about looping and itera...
If you want to do something more elaborate, you could create a script and show a more clear indication that the loop condition became true: #!/bin/bashwhile[!-ddirectory_expected]doecho"`date`- Still waiting"sleep1doneecho"DIRECTORY IS THERE!!!" 3. Using a while loop to manipulate a ...
Iterate the Script Using the Three-Expression “For” LoopThe three-expression “for” loop is the conventional way of using “for” loop for any programming language. The following script shows the use of the three-expression “for” loop in Bash to print the values of an array....
The while loop is another popular and intuitive loop you can use in bash scripts. The general syntax for abash while loopis as follows: while [ condition ]; do [COMMANDS] done For example, the following3x10.shscript uses a while loop that will print the first ten multiples of the number...
for i in "${distros[@]}"; do echo $i done If you run the script, it will display all the distros defined in the array: Ubuntu Fedora Debian Alpine While loop in bash The while loop tests a condition and then keeps on looping as long as the condition is true. ...
Now that we have our “for” loop created in our Bash script, save and exit the file. We must first add the executable permission to execute the script. sudochmod+x<filename.sh> Next, execute the script as shown in the following. Watch how we get the Bash “for” loop iterating the...
Now that we have seen and understand the basic commands of the Bash shell as well as the basic concepts of loops and arrays in Bash, let's go ahead and see a useful script using the loops and arrays together. In our simple example below we'll assume that you want to display a list...
After about 17 seconds we interrupt our script by using CTRL+c, which is the universal method to stop a running process in Bash (besides the stronger and more effective CTRL+z which pauses a process immediately, but that is for another article!) ...
How to pass variable values in this for loop in shell script, Change a variable in a shell script loop [duplicate], Loop Variables and `unset` in Shell Script, Is it possible to make the variable inside nested for loop local
A bash script is simply a plain text file containing a series of commands that the bash shell can read and execute. Bash is the default shell in pre-Catalina macOS, and most Linux distributions. If you’ve never worked with a shell script before, you should begin with the absolute simples...