使用shell脚本如何在换行头和尾部记录的末尾添加字符

Question

我有file.txt

0ABCD文件20210922
16123414662290120210922AB 1455AMSHREY
111612341462300120210922AC 1455AMSHRAEY
11161234414110120210922AB 0271AMSJ
1116 12341491236020210922AR 0271AMSJ
111234141414070120210921AB 0100AMSHKGJ
9000000000005

希望在跳过标头和尾部的记录末尾添加"F"。请告知。感谢

0ABCD文件20210922
16123414662290120210922AB 1455AMSHREYF
111612341462300120210922AC 1455AMSHRAEYF
11161234 14911020120210922AB 0271AMSJF
161123449112360120210922AR 0271AMSJF
161134141404070120210921AB 0100AMSHKGJ
9000000000005

Answer 1

您可以尝试以下操作：

$ awk 'NR > 1 && NF > 1 { $(NF) = $(NF)"F" } { print }' < file.txt