fork compare to exec in linux c program
pid_t pid=fork()
it has 3 situation for the return result pid
0 child
>0 parent process
<0 fork fail
fork create a new process and it parent live alse when the child process had been created
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总览
用iptables -ADC 来指定链的规
则
，-A添加 -D删除 -C 修改
iptables - [RI] chain rule num rule-specification[option]
用iptables - RI 通过规则的顺序指定
iptables -D chain rule num[option]
删除指定规则
iptables -[LFZ] [chain][option]
用iptables -LFZ 链名 [选项]
iptables -[NX] chain
用 -NX ......
1 shutdown:
[NAME
] shutdown - bring the system down
SYNOPSIS
/sbin/shutdown [-t sec] [-arkhncfF] time [warning-message]
DESCRIPTION
shutdown brings the system down in a secure way.&nb ......
一、svn客户端安装及环境配置.
果所在的linux机器上没有安装svn客户端，则首先安装svn客户端：
1. subversion-1.4.3.tar.bz2 subversion-deps-1.4.3.tar.bz2
2. 使用
tar xvfj subversion-1.4.3.tar.bz2
tar xvfj subversion-deps-1.4.3.tar.bz2
解压这两个文件(不要乱了顺序)，此时在当前目录下会出现subvers ......
程序12：类似java 里面的switch case
[root@localhost scripts]# cat sh12.sh
read -p "input comand:" command
case $command in
"fix")
echo "fix system"
;;
"fuck")
echo "fuck you"
;;
*)
echo "what a stupid man!ex>$0 some word"
......
