Awk by Example–转载

原文地址：

http://www.funtoo.org/Awk_by_Example,_Part_1?ref=dzone

http://www.funtoo.org/Awk_by_Example,_Part_2

http://www.funtoo.org/Awk_by_Example,_Part_3

halt7 
operator11 
root0 
shutdown6 
sync5 
bin1 
....etc. 




username: halt     uid:7 
username: operator uid:11 
username: root     uid:0 
username: shutdown uid:6 
username: sync     uid:5 
username: bin      uid:1 
....etc. 




BEGIN { 
        FS=":" 
} 
{ print $1 } 



#!/usr/bin/awk -f
BEGIN {
    FS=":"
}
{ print $1 }








/foo/ { print }

/[0-9]+\.[0-9]*/ { print }


$1 == "fred" { print $3 }

$5 ~ /root/ { print $3 }


{ 
    if ( $5 ~ /root/ ) { 
        print $3 
    }
}



{
    if ( $1 == "foo" ) {
        if ( $2 == "foo" ) {
            print "uno"
        } else {
            print "one"
        }
    } else if ($1 == "bar" ) {
        print "two"
    } else {
        print "three"
    }
}


! /matchme/ { print $1 $3 $4 }


{
    if ( $0!~ /matchme/ ) {
        print $1 $3 $4
    }
}



( $1 == "foo" ) && ( $2 == "bar" ) { print } 




BEGIN { x=0 } 
/^$/  { x=x+1 } 
END   { print "I found " x " blank lines.:)" } 




x="1.01" 
# We just set x to contain the *string* "1.01" 
x=x+1 
# We just added one to a *string* 
print x 
# Incidentally,these are comments:) 


2.01


{ print ($1^2)+1 }








FS="\t+"



FS="[[:space:]]+"



FS="foo[0-9][0-9][0-9]"



NF == 3 { print "this particular record has three fields: " $0 }


{
    if ( NF > 2 ) {
        print $1 " " $2 ":" $3 
    }
}



(NR < 10 ) || (NR > 100) { print "We are on record number 1-9 or 101+" }

{
    #skip header
    if ( NR > 10 ) {
        print "ok,now for the real information!"
    }
}
















Jimmy the Weasel

100 Pleasant Drive

San Francisco,CA 12345