The until Statement
You can use the until
statement to execute a series of commands until a specified condition is true
.
The loop terminates as soon as the specified condition evaluates to true
.
In pdksh
and bash
, the following format is used:
until expressiondo statementsdone
As you can see, the format of the until
statement is similar to that of the while
statement, but the logic is different: In a while
loop, you execute until an expression is false, but in an until
loop, you loop until the expression is true. An important part of this difference is that while
is executed zero or more times (potentially not executed at all), but until
is repeated one or more times, meaning it is executed at least once.
If you want to add the first five ...
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