Shell programming (13) --- WHILE LOOP

The while loop is applicable to scenarios where the number of loops is unknown.

Syntax format: While conditiondo statement ...... Done Note: While is used to execute a loop when the condition is set up. When the condition is invalid, the loop is exited.

Example 1: add the value from 1 to 100.

[[Email protected] Learn] # Cat while1.sh #! /Bin/bashdeclare-I sum = 0 declare-I I = 0 while [$ I-Le 100] Do let sum + = $ I let I + = 1 doneecho $ sum [[ email protected] Learn] # chmod + x while1.sh [[email protected] Learn] #. /while1.sh 5050 [[email protected] Learn] #

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