1.

echo $USER |ENTER|

root

2.

ps |ENTER|

PID TTY TIME CMD
47 hvc0 00:00:00 sh
100 hvc0 00:00:00 ps

3.

ps |ENTER|

PID TTY TIME CMD
47 hvc0 00:00:00 sh
101 hvc0 00:00:00 ps

4.

echo ps > /dev/hvc0 |ENTER|

ps

5.

yes "I am you, and you are me, and we are all, together" |ENTER|

I am me, and me are you, and we are all together
I am me, and me are you, and we are all together
I am me, and me are you, and we are all together
I am me, and me are you, and we are all together
I am me, and me are you, and we are all together

...

I am me, and me are you, and we are all together
I am me, and me are you, and we are all^C

6.

|CTRL| |Z|

I am me, and me are^Z
[1]+ Stopped(SIGTSTP) yes "I am me, and me are you, and we are all together"

7.

ps |ENTER|

kill -s TERM %1 |ENTER|

jobs |ENTER|


PID TTY TIME CMD
47 hvc0 00:00:00 sh
101 hvc0 00:00:04 yes
102 hvc0 00:00:00 ps



[1]+ Terminated yes "I am...

8.

yes "together no more" > /dev/null |ENTER|


9.

|CTRL||Z|

bg %1 |ENTER|

ps -l |ENTER|

^Z [1]+ Stopped(SIGTSTP) yes "together no more" > /dev/null
[1] yes "together no more" > /dev/null &
F S UID PID PPID C PRI NI ADDR SZ WCHAN TTY TIME CMD
0 S 0 47 1 0 80 0 - 1522 sinitt hvc0 00:00:00 sh
0 T 0 274 47 67 80 0 - 1136 do_sig hvc0 00:05:22 yes
0 R 0 279 47 0 80 0 - 2108 - hvc0 00:00:00 ps

10.

?????????? |ENTER|
|
ENTER|

[1]+ Terminated yes "together no more" > /dev/nul

11.

bash |ENTER|

ps |ENTER|

PID TTY TIME CMD
47 hvc0 00:00:01 sh
300 hvc0 00:00:00 bash
319 hvc0 00:00:00 ps

12.

yes "hi" > /dev/null 2>&1 |ENTER|

|CTRL||Z|

bg %1 |ENTER|

ps |ENTER|

^Z [1]+ Stopped yes "hi" > /dev/null 2>&1

[1]+ yes "hi" > /dev/null 2>&1 &

PID TTY TIME CMD
47 hvc0 00:00:01 sh
300 hvc0 00:00:00 bash
402 hvc0 00:03:23 yes
403 hvc0 00:00:00 ps

13.

exit |ENTER|

ps |ENTER|

jobs |ENTER|

kill -s TERM %1 |ENTER|

ps |ENTER|

kill -s TERM 402 |ENTER|

ps |ENTER|


PID TTY TIME CMD
47 hvc0 00:00:01 sh
402 hvc0 00:03:23 yes
404
hvc0 00:00:00 ps

sh: kill: %1: no such job

PID TTY TIME CMD
47 hvc0 00:00:01 sh
402 hvc0 00:03:23 yes
404
hvc0 00:00:00 ps

PID TTY TIME CMD
47 hvc0 00:00:01 sh
406
hvc0 00:00:00 ps

14.

ls -sh hello.c

ls -sh juan

ls -hs hello.c > ls.log

cat ls.log

ls -hs juan > ls.log

cat ls.log

ls -hs juan > log.log 2>&1

cat ls.log






4.0K hello.c

ls: cannot access 'juan': No such file or directory



4.0K hello.c

ls: cannot access 'juan': No such file or directory





ls: cannot access 'juan': No such file or directory







cat ls.log

Enter your answers:


ls -sh hello.c



ls -sh juan


15.

ls -hs hello.c > ls.log


cat ls.log


ls -hs juan > ls.log


cat ls.log


ls -hs juan > log.log 2>&1

16.

top |ENTER|




top - 19:27:56 up 6:21, 0 users, load average: 0.06, 0.02, 0.00
Tasks: 21 total, 1 running, 20 sleeping, 0 stopped, 0 zombie
%Cpu(s):0.7 us, 0.7 sy, 0.0 ni, 98.7 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0st
MiB Mem : 246.1 total, 237.0 free, 5.6 used, 3.5 buff/cache
MiB Swap: 0.0 total, 0.0 free, 0.0 used. 235.8 avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1574 root 20 0 8848 2320 1740 R 2.0 0.9 0:00.69 top
1 root 20 0 2896 1424 1164 S 0.0 0.6 0:00.75 init
2 root 20 0 0 0 0 S 0.0 0.0 0:00.00 kthreadd
3 root 20 0 0 0 0 I 0.0 0.0 0:00.00 kworker/0+
4 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 kworker/0+
5 root 20 0 0 0 0 I 0.0 0.0 0:00.00 kworker/u+
6 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 mm_percpu+
7 root 20 0 0 0 0 S 0.0 0.0 0:01.84 ksoftirqd+
8 root 20 0 0 0 0 S 0.0 0.0 0:00.07 kdevtmpfs
9 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 netns
10 root 20 0 0 0 0 S 0.0 0.0 0:00.00 oom_reaper
11 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 writeback
12 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 crypto
13 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 kblockd
14 root 20 0 0 0 0 S 0.0 0.0 0:00.00 kswapd0
15 root 20 0 0 0 0 I 0.0 0.0 0:00.14 kworker/0+
32 root 20 0 0 0 0 S 0.0 0.0 0:00.00 khvcd
42 root 20 0 1948 1064 788 S 0.0 0.4 0:00.42 dhcpcd
47 root 20 0 6088 2224 1708 S 0.0 0.9 0:01.90 sh
78 root 20 0 0 0 0 I 0.0 0.0 0:00.20 kworker/u+
488 root 20 0 6060 2396 1808 S 0.0 1.0 0:01.87 bash