Practical UNIX

awk

Aho, Weinberger, and Kernighan’s C-like programming language

Standard Input: Used only if no list-of-files is given

Standard Output: Used to display results

Note

On some systems, use nawk (new awk) or gawk (GNU awk).

Using awk from the command line to display selected lines:

awk '$n == "string"' [list-of-files]
   (display line if field n equals string)
awk '$n > 3.5' [list-of-files]
   (display line if field n is greater than value.
    can also test ==, !=, >, <, >=, <=)
awk '$n ~ /R.E./' [list-of-files]

Using awk to display selected fields:

awk '{print $1, $5, $0}' [list-of-files]
awk '{if ($5 > 20000) $5=20000} {print "file: " $9         "       " $5}'
awk '{ printf("Name: %16s, Size: %5d, Blocks:                   %6.2f\n", $9, $5,
$5/512)}'

Using awk from the command line ...