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hpr2804 :: Awk Part 13: Fix-Width Field Processing

In this episode, I discuss how to deal with fix-width field text files using Awk

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Hosted by Mr. Young on 2019-05-02 is flagged as Explicit and is released under a CC-BY-SA license.
bash, linux, cli, command-line, awk. (Be the first).
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Duration: 00:06:21

Learning Awk.

Episodes about using Awk, the text manipulation language. It comes in various forms called awk, nawk, mawk and gawk, but the standard version on Linux is GNU Awk (gawk). It's a programming language optimised for the manipulation of delimited text.

Basic usage

Use the FIELDWIDTHS = "n1 n2 n3 ..." annotation in the BEGIN section of an awk command to specify the widths of the fields.

For instance, the following file has widths of 20, 10, and 12 characters.

NAME                STATE     TELEPHONE
John Smith          WA        418-311-4111
Mary Hartford       CA        319-219-4341
Evan Nolan          IL        219-532-5301
Boris Ratinski      NC        201-553-5555

Below is an example of processing such a file:

BEGIN  { FIELDWIDTHS = "20 10 12" }
NR > 1 {
    name = $1
    state = $2
    phone = $3
    sub(/ +$/, "", name)
    sub(/ +$/, "", state)
    sub(/ +$/, "", phone)
    printf("%s lives in %s. The phone number is %s.\n", name, state, phone)

Then you can run the command:

awk -f process_fixed_width.awk fixed_width.txt


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