一个awk解析文件的例子

a.txt,每三行一个记录:

 

eth0
ge1
00:00.1
eth1
ge2
00:00.2
eth2
ge3
00:00.3

b.awk:

BEGIN {
    FS="\n"
    RS=""
    ORS=""
}
{
    i=1
    while(i<NF){
        print $i "\t"
        if(i%3 == 0)
            print "\n"
        i++
    }
    print $NF "\n"
}


FS          The input field separator, a space by default.

RS          The input record separator, by default a newline.
NF          The number of fields in the current input record.
NR          The total number of input records seen so far.
OFMT        The output format for numbers, "%.6g", by default.
OFS         The output field separator, a space by default.
ORS         The output record separator, by default a newline.

运行 $awk -f b.awk a.txt

eth0 ge1 00:00.1
eth1 ge2 00:00.2
eth2 ge3 00:00.3