(echo "stats";sleep 2)|telnet 172.*.*.* 12000

#!/bin/sh

#通过传入ip 以及端口，发送指令获得返回数据
#copyright chengmo qq:8292669

#函数往往放到最上面
function sendmsg()
{
    msg=$1;
    echo  "$1">&8;
    getout;
}
#向socket通道发送指令，并且调用获得返回参数

function getout()
{  
    #read 命令 -u 从打开文件描述符 8 读取数据，-d读取数据忽略掉:\r换行符
    while read -u 8 -d $'\r' name;
    do
        if [ "${name}" == "END"  -o "${name}" == "ERROR" ];then
            break;
        fi;
        echo $name;
    done
}
#由于：memcached每次通讯完毕，会返回：END或者ERROR(出错），通过判断是否是"END"觉得读取是不是结束，否则循环不会停止

if [ $# -lt 2 ];then
    echo "usage:$0 host port [command]";
    exit 1;
fi;

[[ $# -gt 2 ]]&&command=$3;

#设置默认值 如果command为定义则为：stats
command="${command=stats}";
host="$1";
port="$2";



exec 8<>/dev/tcp/${host}/${port};
#打开通向通道是8

if [ "$?" != "0" ];then
    echo "open $host  $port fail!";
    exit 1;
fi

sendmsg "$command";
#发送指定命令


sendmsg "quit";
#发送退出通向命令


exec 8<&-;
exec 8>&-;
#关闭socket通道

exit 0;

[chengmo@centos5 shell]$ (echo -e "HEAD / HTTP/1.1\n\n\n\n\n";sleep 2)|telnet www.baidu.com 80
Trying 220.181.6.175...
Connected to www.baidu.com.
Escape character is '^]'.
HTTP/1.1 200 OK
Date: Thu, 21 Oct 2010 15:51:58 GMT
Server: BWS/1.0
Content-Length: 6218
Content-Type: text/html;charset=gb2312
Cache-Control: private
Expires: Thu, 21 Oct 2010 15:51:58 GMT
Set-Cookie: BAIDUID=0B6A01ACECD5353E4247E088A8CB345A:FG=1; expires=Thu, 21-Oct-40 15:51:58 GMT; path=/; domain=.baidu.com
P3P: CP=" OTI DSP COR IVA OUR IND COM "
Connection: Keep-Alive
#成功了！加入sleep 居然可以了，sleep 改成1秒也可以

[chengmo@centos5  shell]$ exec 8<>/dev/tcp/127.0.0.1/22
[chengmo@centos5  shell]$ ls -l /proc/self/fd/
总计 0
lrwx------ 1 chengmo chengmo 64 10-21 23:05 0 -> /dev/pts/0
lrwx------ 1 chengmo chengmo 64 10-21 23:05 1 -> /dev/pts/0
lrwx------ 1 chengmo chengmo 64 10-21 23:05 2 -> /dev/pts/0
lr-x------ 1 chengmo chengmo 64 10-21 23:05 3 -> /proc/22185/fd
lrwx------ 1 chengmo chengmo 64 10-21 23:05 8 -> socket:[15067661]

#文件描述符8，已经打开一个socket通讯通道，这个是一个可以读写socket通道,因为用："<>"打开
[chengmo@centos5  shell]$ exec 8>&-
#关闭通道
[chengmo@centos5  shell]$ ls -l /proc/self/fd/
总计 0
lrwx------ 1 chengmo chengmo 64 10-21 23:08 0 -> /dev/pts/0
lrwx------ 1 chengmo chengmo 64 10-21 23:08 1 -> /dev/pts/0
lrwx------ 1 chengmo chengmo 64 10-21 23:08 2 -> /dev/pts/0
lr-x------ 1 chengmo chengmo 64 10-21 23:08 3 -> /proc/22234/fd

#!/bin/sh
#testhttphead.sh
#实现通过主机名，端口读取web 服务器header信息
#copyright chengmo,qq:8292669

if(($#<2));then
    echo "usage:$0 host port";
    exit 1;
fi
#如果参数缺失，退出程序，返回状态1

exec 6<>/dev/tcp/$1/$2 2>/dev/null;
#打开host的port 可读写的socket连接，与文件描述符6连接

if(($?!=0));then
    echo "open $1 $2 error!";
    exit 1;
fi
#如果打开失败，$?返回不为0，终止程序

echo -e "HEAD / HTTP/1.1\n\n\n\n\n">&6;
#将HEAD 信息，发送给socket连接

cat<&6;
#从socket读取返回信息，显示为标准输出

exec 6<&-;
exec 6>&-;
#关闭socket的输入，输出

exit 0;