#!/bin/bash# test7:用于对比各种脚本程序执行方式的区别echo"The variable var1 is"$var1echo"The environment variable env1 is"$env1echo"The current shell PID is $$"
1. 使用绝对路径执行脚本
测试过程
root@Dell-Tom:~# var1=1
root@Dell-Tom:~# export env1=1
root@Dell-Tom:~# echo "The current shell PID is" $$
The current shell PID is 564
root@Dell-Tom:~# /root/script_test/test7
The variable var1 is
The environment variable env1 is 1
The current shell PID is 587
root@Dell-Tom:~# var1=1
root@Dell-Tom:~# export env1=1
root@Dell-Tom:~# echo "The current shell PID is" $$
The current shell PID is 564
root@Dell-Tom:~# test7
The variable var1 is
The environment variable env1 is 1
The current shell PID is 640
root@Dell-Tom:~# var1=1
root@Dell-Tom:~# export env1=1
root@Dell-Tom:~# echo "The current shell PID is" $$
The current shell PID is 564
root@Dell-Tom:~# . script_test/test7
The variable var1 is 1
The environment variable env1 is 1
The current shell PID is 564
root@Dell-Tom:~# var1=1
root@Dell-Tom:~# export env1=1
root@Dell-Tom:~#
root@Dell-Tom:~# echo "The current shell PID is" $$
The current shell PID is 564
root@Dell-Tom:~#
root@Dell-Tom:~# ./script_test/test7
The variable var1 is
The environment variable env1 is 1
The current shell PID is 648