> echo $SHELL
/bin/bash
> echo $$
4834
> ps -o pid,ppid,pgid,sid,tpgid,tty,comm
PID PPID PGID SID TPGID TT COMMAND
4834 4827
4834
4834 18504 pts/3 bash
18504 4834
18504
4834
18504
pts/3 ps
> ps -o pid,ppid,pgid,sid,tpgid,tty,comm &
[1] 18871
>
PID PPID PGID SID TPGID TT COMMAND
4834 4827
4834
4834
4834
pts/3 bash
18871 4834
18871
4834 4834 pts/3 ps
[1]+ Done ps -o pid,ppid,pgid,sid,tpgid,tty,comm
> ps -o pid,ppid,pgid,sid,tpgid,tty,comm | cat
PID PPID PGID SID TPGID TT COMMAND
4834 4827
4834
4834 18887 pts/3 bash
18887 4834
18887
4834
18887
pts/3 ps
18888 4834
18887
4834
18887
pts/3 cat
> ps -o pid,ppid,pgid,sid,tpgid,tty,comm | cat &
[1] 18891
>
PID PPID PGID SID TPGID TT COMMAND
4834 4827
4834
4834
4834
pts/3 bash
18890 4834
18890
4834 4834 pts/3 ps
18891 4834
18890
4834 4834 pts/3 cat
[1]+ Done ps -o pid,ppid,pgid,sid,tpgid,tty,comm | cat
> ps -o pid,ppid,pgid,sid,tpgid,tty,comm | cat | tee
PID PPID PGID SID TPGID TT COMMAND
4834 4827 4834 4834 28434 pts/3 bash
28434 4834
28434
4834
28434
pts/3 ps
28435 4834
28434
4834
28434
pts/3 cat
28436 4834
28434
4834
28434
pts/3 tee
> ps -o pid,ppid,pgid,sid,tpgid,tty,comm | cat | tee &
[1] 28447
>
PID PPID PGID SID TPGID TT COMMAND
4834 4827
4834
4834
4834
pts/3 bash
28445 4834
28445
4834 4834 pts/3 ps
28446 4834
28445
4834 4834 pts/3 cat
28447 4834
28445
4834 4834 pts/3 tee
[1]+ Done ps -o pid,ppid,pgid,sid,tpgid,tty,comm | cat | tee
> echo $SHELL
/bin/bash
> echo $$
6183
> ps -o pid,ppid,pgid,sid,tpgid,tty,comm
PID PPID PGID SID TPGID TT COMMAND
6183 6179 6183 6183 7358 pts/7 bash
7358
6183 7358 6183 7358 pts/7 ps
> (ps -o pid,ppid,pgid,sid,tpgid,tty,comm)
PID PPID PGID SID TPGID TT COMMAND
6183 6179 6183 6183 7385 pts/7 bash
7385
6183 7385 6183 7385 pts/7 ps
> { ps -o pid,ppid,pgid,sid,tpgid,tty,comm; }
PID PPID PGID SID TPGID TT COMMAND
6183 6179 6183 6183 7388 pts/7 bash
7388
6183 7388 6183 7388 pts/7 ps