但是默认配置，不应该会限制sudo后不能监听端口

happy@happy:~/demo$ g++ 1.cpp
happy@happy:~/demo$ ./a.out
正在监听端口 8090...
^C
happy@happy:~/demo$ sudo ./a.out
请输入密码:
验证成功
绑定失败
happy@happy:~/demo$ sudo gdb ./a.out
GNU gdb (Uos 8.2.1.1-1+security) 8.2.1
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License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
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Type "show copying" and "show warranty" for details.
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Type "show configuration" for configuration details.
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<http://www.gnu.org/software/gdb/bugs/>.
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For help, type "help".
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Reading symbols from ./a.out...(no debugging symbols found)...done.
(gdb) run
Starting program: /home/happy/demo/a.out
正在监听端口 8090...
^C
Program received signal SIGINT, Interrupt.
0x0000007fbf3a3740 in __libc_accept (fd=3, addr=..., len=0x7fffffe084) at ../sysdeps/unix/sysv/linux/accept.c:26
26../sysdeps/unix/sysv/linux/accept.c: 没有那个文件或目录.
(gdb) quit
A debugging session is active.

Inferior 1 [process 21828] will be killed.

Quit anyway? (y or n) y
happy@happy:~/demo$ sudo -i
root@happy:~# pwd
/root
root@happy:~# /home/happy/demo/a.out
正在监听端口 8090...


【 在 Bernstein 的大作中提到: 】
: 不同系统sudo之后权限的配置有一定不同
:
--
修改:z16166 FROM 123.118.191.*
FROM 123.118.191.*