Linux Common basic commands: The-awk mode usage of the Three Musketeers command (1)

Again, the awk basic syntax format:

awk [Options] ' Pattern {Action} ' file1 file2

The previous article discussed two types of pattern (BEGIN, END), and this article explores other pattern (pattern) usages again.

What is the pattern? A pattern is a matching condition that satisfies a condition and executes the subsequent action.

1, without any pattern of usage, called null mode

[Email protected]:~/linux/awkawk'{print}'   man Lisi

2, by the built-in variable NF, the row of the print column equals 3

[Email protected]:~/linux/awkcatlisi[ Email protected]:~/linux/awkawk'nf==3{print}'    Man

3, you can also use relational operators, relational operators, similar to most programming languages:

[Email protected]:~/linux/awk$Catghostwu.txt GHOSTWU - MansZhangsan ALisi[email protected]:~/linux/awk$awk '$1== "Ghostwu" {print}'ghostwu.txt GHOSTWU - Mans[email protected]:~/linux/awk$awk 'nf>1 "{print}"'ghostwu.txt GHOSTWU - MansZhangsan A

4, previously introduced by begin, End mode

[Email protected]:~/linux/awkawk'begin{print ' name ', ' age ', ' gender '} {print $, $ $, $ $} end{ Print "Package Sky", "Man"}' $ Man ' Lisi    $ Mans

Linux Common basic commands: The-awk mode usage of the Three Musketeers command (1)