bash姿势-没有管道符执行结果相同于管道符

听起来比较别口：

直接看代码：

shell如下：

[root@sevck_linux ~]# </etc/passwd grep root
root:x:0:0:root:/root:/bin/bash
operator:x:11:0:operator:/root:/sbin/nologin
[root@sevck_linux ~]# cat /etc/passwd | grep root
root:x:0:0:root:/root:/bin/bash
operator:x:11:0:operator:/root:/sbin/nologin
[root@sevck_linux ~]# < <(echo this is a test) wc 
      1       4      15
[root@sevck_linux ~]# echo this is a test | wc
      1       4      15
[root@sevck_linux ~]# 

just do it .