Before starting the while loop it checks the condition, if it evaluates to true then the body of the loop will execute and continues the same process until the condition evaluates to false. As a result, you only see the first line processed, because ssh consumes the rest of the file and your while loop terminates.. To prevent this, pass the -n option to your ssh command to make it read from /dev/null instead of stdin. num stores the number whose factorial is to be calculated.. factorial variable stores the result of factorial.. counter is a temporary variable to store the given number and gets decremented in the while loop. If the condition is met it execute the following code and then again goes to verify condition. while CONTROL-COMMAND; do CONSEQUENT-COMMANDS; done. Please contact the developer of this form processor to improve this message. Let us consider an example for while loop and discuss the flow of the while loop using the example as below: a=0 It is the best tool to use when you need to execute a set of statements repeated based on a condition. While Loop. while IFS = read -r line command on $line The break command terminates the loop (breaks out of it), while continue causes a jump to the next iteration of the loop, skipping all the remaining commands in that particular loop cycle. n=$((n+1)) The while statement starts with the while keyword, followed by the conditional expression. To read a text file line-by-line, use the following syntax: The general syntax for a while loop is as follows: while [ condition ]; do [COMMANDS] done. … This calling can be done in many ways one of the ways is looping. As a result, we have for and while loops in the Bourne shell. Learn More{{/message}}, Next FAQ: HowTo: Display / Echo Path Settings In Linux / UNIX / *BSD, Previous FAQ: HowTo: Use Oracle / MySQL SQL Commands In UNIX Shell Scripts, Linux / Unix tutorials for new and seasoned sysadmin || developers, ### just skip printing $i; if it is 3 or 6 ###, ### resumes iteration of an enclosing for loop ###, ### resumes iteration of an enclosing while loop if $i is 3 or 6 ###, Bash Continue Command / Script On The Next Line, HowTo: Bash For While Loop Through File Contents Script, Bash / KSH: Define Delimiter (IFS) While Using read Command. Next the script runs a while loop. Let us discuss while loop with different examples and discuss what it is trying to do with that particular while loop and how we need to write and what things need to take care of while writing. factorial=1 So, while will continue execution until it reads all the lines from the file and then terminate the loop and the output of the above program will change based on the content of the file we are reading. Use the continue statement to return to the top of the loop by skipping the rest of the commands in in the loop. Commands affecting loop behavior. If this file name contains no capital letters, the script executes the continue statement, forcing the shell to go to the beginning of the for loop and get the next file name. In the above syntax example, until the condition evaluates to true all the commands command1, command2 between do and done keywords will be executed and while loop will terminate when the condition is not satisfied and proceeds to statement next to the done keyword. In a script, the command following the done statement is executed. As the condition becomes false, the execution moves to the next line of code outside of the while loop. Example – Iterate over elements of an Array; Example – Consider white spaces in String as word separators command1 done In Linux we use loops via Bash, Python to make automation like password script, counting script. counter=$(( $counter - 1 )) Let us write a while loop to calculate the factorial of a given number and display it on the console. A sample shell script to print number from 1 to 6 but skip printing number 3 and 6 using a for loop: A sample shell script to print number from 1 to 6 but skip printing number 3 and 6 using a while loop: Your email address will not be published. Basic questions way, i goes shell script while loop next by 1 each time through loop... Then no statement will be executed and the program will jump to the code! 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