grep 中 '.'的含义是什么?
# ls -l |grep .jiudao
drwxr-x--- 4 root system 256 Jul 27 2009 jiudao
drwxr-x--- 4 root system 256 Jul 27 2009 jiudao.1
# ls -l |grep jiudao
drwxr-x--- 4 root system 256 Jul 27 2009 jiudao
drwxr-x--- 4 root system 256 Jul 27 2009 jiudao.1
# ls -l |grep .....jiudao
drwxr-x--- 4 root system 256 Jul 27 2009 jiudao
drwxr-x--- 4 root system 256 Jul 27 2009 jiudao.1
#
输出都是一样的
"." 代表着可以可以被忽略?