在我们的AES 256位加密/解密程序在等待用户输入密码时，它能实时检测到有其它进程试图读它的输入：

[root@rl5 ~]# fcrypt -e - /etc/hosts
Please enter the key string:
Warning: pid=29171 is using your tty!
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root     29171 28993  0 10:30 pts/1    00:00:00 dd if /dev/pts/2
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Warning: pid=29171 is using your tty!
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root     29171 28993  0 10:30 pts/1    00:00:00 dd if /dev/pts/2
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