Linux C Socket 编程 如何知道(检测)某个端口是否已建立监听? - V2EX
V2EX = way to explore
V2EX 是一个关于分享和探索的地方
现在注册
已注册用户请  登录
请不要在回答技术问题时复制粘贴 AI 生成的内容
b00tyhunt3r
V2EX    程序员

Linux C Socket 编程 如何知道(检测)某个端口是否已建立监听?

  •  
  •   b00tyhunt3r 2020-01-13 09:01:43 +08:00 2289 次点击
    这是一个创建于 2107 天前的主题,其中的信息可能已经有所发展或是发生改变。

    简单说想实现一个本地网络 p2p 通信程序,用户在控制台输入命令,程序开始检测本地网络 9990 这个端口,如果 9990 为空闲端口,则在此建立监听。如果 9990 位置已经有其他用户使用本程序建立好的监听,则 connect 加入。如果端口被其他程序占用,报错。 那么该如何得到端口状态呢?谢谢解答!!!!

    mrcn
        1
    mrcn  
       2020-01-13 09:23:42 +08:00 via Android
    记得是如果占用了,listen 还是 bind 会出错,返回值-1。
    chu1337
        2
    chu1337  
       2020-01-13 10:41:53 +08:00
    bind:

    ```
    RETURN VALUES
    Upon successful completion, a value of 0 is returned. Otherwise, a value of -1 is returned and the global integer variable errno is set to indicate the
    error.
    ```
    paoqi2048
        3
    paoqi2048  
       2020-01-13 11:00:46 +08:00
    bind error: EADDRINUSE: The given address is already in use.
    关于     帮助文档     自助推广系统     博客     API     FAQ     Solana     3862 人在线   最高记录 6679       Select Language
    创意工作者们的社区
    World is powered by solitude
    VERSION: 3.9.8.5 25ms UTC 10:25 PVG 18:25 LAX 03:25 JFK 06:25
    Do have faith in what you're doing.
    ubao msn snddm index pchome yahoo rakuten mypaper meadowduck bidyahoo youbao zxmzxm asda bnvcg cvbfg dfscv mmhjk xxddc yybgb zznbn ccubao uaitu acv GXCV ET GDG YH FG BCVB FJFH CBRE CBC GDG ET54 WRWR RWER WREW WRWER RWER SDG EW SF DSFSF fbbs ubao fhd dfg ewr dg df ewwr ewwr et ruyut utut dfg fgd gdfgt etg dfgt dfgd ert4 gd fgg wr 235 wer3 we vsdf sdf gdf ert xcv sdf rwer hfd dfg cvb rwf afb dfh jgh bmn lgh rty gfds cxv xcv xcs vdas fdf fgd cv sdf tert sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf shasha9178 shasha9178 shasha9178 shasha9178 shasha9178 liflif2 liflif2 liflif2 liflif2 liflif2 liblib3 liblib3 liblib3 liblib3 liblib3 zhazha444 zhazha444 zhazha444 zhazha444 zhazha444 dende5 dende denden denden2 denden21 fenfen9 fenf619 fen619 fenfe9 fe619 sdf sdf sdf sdf sdf zhazh90 zhazh0 zhaa50 zha90 zh590 zho zhoz zhozh zhozho zhozho2 lislis lls95 lili95 lils5 liss9 sdf0ty987 sdft876 sdft9876 sdf09876 sd0t9876 sdf0ty98 sdf0976 sdf0ty986 sdf0ty96 sdf0t76 sdf0876 df0ty98 sf0t876 sd0ty76 sdy76 sdf76 sdf0t76 sdf0ty9 sdf0ty98 sdf0ty987 sdf0ty98 sdf6676 sdf876 sd876 sd876 sdf6 sdf6 sdf9876 sdf0t sdf06 sdf0ty9776 sdf0ty9776 sdf0ty76 sdf8876 sdf0t sd6 sdf06 s688876 sd688 sdf86