AWK variables

We saw how to use data fields such as $1 and $2. Also, we saw the NR field, which holds the number of processed lines, but there are more built-in variables that AWK offers to simplify work more and more.

  • FIELDWIDTHS: Specifies the field width
  • RS: Specifies the record separator
  • FS: Specifies the field separator
  • OFS: Specifies the output separator, which is a space by default
  • ORS: Specifies the output separator
  • FILENAME: Holds the processed file name
  • NF: Holds the line being processed
  • FNR: Holds the record which is processed
  • IGNORECASE: Ignores character case

These variables can help you a lot in many cases. Let's assume that we have the following file:

John Doe 15 back street (123) 455-3584 Mokhtar Ebrahim 10 Museum street ...

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