Which of the following is not a pre-defined AWK variable?

Keep practicing — related questions

• Which of the following is/are in built function of AWK in unix?
• Which of the following is the awk built in functions?
• which among the following is not a type of awk
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• Which command is used to get the entire line using awk?
• Which among the following is not a shell type
• What is Output - awk 'BEGIN { if (length($0) > max) max= length($0) } | END { print max }' test.txt
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