linux提取文件最后一行,sed或awk处理文件最后一行的实现方法

时间:2025-03-27 21:30:13

有如下的文本:

abcd 1234 fds

2011 550

1023 832er 1231

要求处理后如下所示:

abcd 1234 fds

2011 550

total1:1023 total2:832er 12end

判断如果是文本最后一行则在第一列前面加total1:,第二列加total2:, 第三列后面减掉后面两个字符并加end。

分别用sed与awk来实现。

sed:

echo 'abcd 1234 fds

2011 550

1023 832er 1231' |sed -r '$s/([^ ]*)( )([^ ]*)( )(..).*$/total1:\1\2total:\3\4\5end/'

abcd 1234 fds

2011 550

total1:1023 total:832er 12end

awk:

awk 'NR>1{print a}{a=$0}END{$1="total1:"$1;$2="total2:"$2;print gensub(/..$/,"end",$0)}' file

awk 'BEGIN{getline a}{print a;a=$0}END{$1="total1:"$1;$2="total2:"$2;$3=gensub(/..$/,"end",1,$3);print}'

awk '{if(!getline line){print "total1:"$1" total2:"$2" "gensub(/..$/,"end",1,$3)}else{print line?$0 RS line:$0}}'