"x[^ ]*"与"x[0-9]*"

yufeiluo

debian8@debian:~$ echo " x  x1 x2 y1 z1  x345" |awk -v RS="x[^ ]*" '$0=RT'
x
x1
x2
x345

debian8@debian:~$ echo " x  x1 x2 y1 z1  x345" |awk -v RS="x[0-9]*" '$0=RT'
x
x1
x2
x345
为何echo " x  x1 x2 y1 z1  x345" |awk -v RS="x[^ ]*" '$0=RT' 的输出结果多了个空行？

1cpuer

^$
shell 数据库段落分隔符
# echo -e '123 \n\n a'
123

a

linux sed
模式空间

# echo abcdef | sed 's/./\n&/g'

a
b
c
d
e
f

^$abcdef^$
linux sed command 数据处理（结果）模式空间
：个人认为