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Control Statements in Actions

Control statements, such as if, while, and so on, control the flow of execution in awk programs. Most of the control statements in awk are patterned on similar statements in C.

All the control statements start with special keywords, such as if and while, to distinguish them from simple expressions. Many control statements contain other statements. For example, the if statement contains another statement that may or may not be executed. The contained statement is called the body. To include more than one statement in the body, group them into a single compound statement with curly braces, separating them with newlines or semicolons.

• If Statement: Conditionally execute some awk statements.
• While Statement: Loop until some condition is satisfied.
• Do Statement: Do specified action while looping until some condition is satisfied.
• For Statement: Another looping statement, that provides initialization and increment clauses.
• Break Statement: Immediately exit the innermost enclosing loop.
• Continue Statement: Skip to the end of the innermost enclosing loop.
• Next Statement: Stop processing the current input record.
• Nextfile Statement: Stop processing the current file.
• Exit Statement: Stop execution of awk.