分类：
2011-03-26 22:36:01
原文地址：理解 ps 参数 tty, a 作者：titer1
感受：unp的命令，实践出真知啊》
unp原书源：
We can also use the ps command to check the status and relationship of these processes.
linux % ps -t pts/6 -o pid,ppid,tty,stat,args,wchan
PID PPID TT STAT COMMAND WCHAN
22038 22036 pts/6 S -bash wait4
17870 22038 pts/6 S ./tcpserv01 wait_for_connect
19315 17870 pts/6 S ./tcpserv01 tcp_data_wait
19314 22038 pts/6 S ./tcpcli01 127.0 read_chan
(We have used very specific arguments to ps to only show us the information that pertains to this discussion.) In this output, we ran the client and server from the same window (pts/6, which stands for pseudo-terminal number 6). The PID and PPID columns show the parent and child relationships. We can tell that the first tcpserv01 line is the parent and the second tcpserv01 line is the child since the PPID of the child is the parent's PID. Also, the PPID of the parent is the shell (bash).
问题当我键入后，失败：
os66@liuliu-os66:~/Downloads/fscap$ ps -t pts/6 -o pid,ppid,tty,stat,args,wchan
ERROR: TTY could not be found.
改变命令后：
os66@liuliu-os66:~/Downloads/fscap$ ps a -o pid,ppid,tty,stat,args,wchan
PID PPID TT STAT COMMAND WCHAN
993 1 tty4 Ss+ /sbin/getty -8 38400 tty4 n_tty_read
995 1 tty5 Ss+ /sbin/getty -8 38400 tty5 n_tty_read
1003 1 tty2 Ss+ /sbin/getty -8 38400 tty2 n_tty_read
1004 1 tty3 Ss+ /sbin/getty -8 38400 tty3 n_tty_read
1006 1 tty6 Ss+ /sbin/getty -8 38400 tty6 n_tty_read
1189 1171 tty7 Ss+ /usr/bin/X :0 -br -verbose poll_schedule_timeout
1706 1 tty1 Ss+ /sbin/getty -8 38400 tty1 n_tty_read
14776 2844 pts/2 Ss bash wait
14926 14776 pts/2 S+ FSCapture.exe pipe_wait
15106 2844 pts/1 Ss bash wait
15189 2844 pts/3 Ss bash wait
15237 2844 pts/4 Ss bash wait
15289 15189 pts/3 S+ /bin/bash n_tty_read
15333 15289 pts/3 S ./S01 inet_csk_wait_for_connect
15335 15106 pts/1 S+ ./C01 127.0.0.1 n_tty_read
15336 15333 pts/3 S ./S01 sk_wait_data
15358 15237 pts/4 R+ ps a -o pid,ppid,tty,stat,a -
小结：
我使用的终端不一定是 tty…
其中，参数a意思：all w/ tty, including other users
后续工作ps 的参数很多，请慢慢品味：
