Awk¶

Basic structure of an awk program:

In short, an Domain Specified Language for pattern matching.

pattern { action }

Pass shell variables into awk

awk '{print $home}' home=$HOME

Use regular expression

The regex must be enclosed by slashes(/), and comes after the operator.
/regex_pattern/ { print 1 }

Print remaining columns: 1

{ $1=""; print $0 }

Print a character arbitrary times:

printf is not possible to do this, use for loop.
{ for(c=0;c<50;c++) printf "-"; printf "\n" }

参见