AWK學習筆記

cat  file.txt

Mike Harrington:[phone]:250:100:175
Christian Dobbins:[phone]:155:90:201
Susan Dalsass:[phone]:250:60:50
Archie McNichol:[phone]:250:100:175
Jody Savage:[phone]:15:188:150
Guy Quigley:[phone]:250:100:175
Dan Savage:[phone]:450:300:275
Nancy McNeil:[phone]:250:80:75
John Goldenrod:[phone]:250:100:175
Chet Main:[phone]:50:95:135
Tom Savage:[phone]:250:168:200
Elizabeth Stachelin:[phone]:175:75:300

 

只要4個字符姓名

awk  

 

 

length 用法  

 

awk '{if(length($1)==4 print $1} ' file.txt

 

 

--posix  參數 用法

 

awk --posix  '$1 ~/^[a-zA-Z]{4}$/{print $0}' file.txt