1. Android的netstat

    netstat代码如下所示：

int netstat_main(int argc, char *argv[])
{
    printf("Proto Recv-Q Send-Q Local Address          Foreign Address        State\n");
    ipv4("/proc/net/tcp",  "tcp");
    ipv4("/proc/net/udp",  "udp");
    ipv6("/proc/net/tcp6", "tcp6");
    ipv6("/proc/net/udp6", "udp6");
    return 0;
}

如：cat /proc/net/tcp6内容如下：

# cat /proc/net/tcp6                               
  sl  local_address                         remote_address                        st tx_queue rx_queue tr tm->when retrnsmt  

                                                                         uid     timeout inode
   0: 00000000000000000000000000000000:EA60 00000000000000000000000000000000:0000 0A 00000000:00000000 00:00000000 00000000 10031        0 8220 1 eded9b80 300 0 0 2 -1
   1: 00000000000000000000000000000000:1873 00000000000000000000000000000000:0000 0A 00000000:00000000 00:00000000 00000000 10071        0 8214 1 eded8000 300 0 0 2 -1
   2: 0000000000000000FFFF00008204A8C0:E066 0000000000000000FFFF0000CEEB7D4A:0050 08 00000000:00000001 00:00000000 00000000  1000        0 5015 1 eded8b00 21 4 22 10 -1
   3: 0000000000000000FFFF00008204A8C0:EA60 0000000000000000FFFF00005B04A8C0:CECD 01 00000000:00000000 00:00000000 00000000 10031        0 8376 1 ededa100 300 0 0 10 -1

如对于端口EA60 (60000)的uid为10031，大于10000的uid为app。

2. 在pid中如何寻找对应的uid

   如我的10031在app_31中。

app_31    2761  1378  454512 28132 ffffffff 400e7ae8 S cn.mytest.test

# cat /proc/2761/cgroup                              
2:cpu:/bg_non_interactive
1:cpuacct:/uid/10031

其实很简单，app_xx对应的uid为10000+xx