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This article shares with you the content of a sample analysis of the Linux command for Halloween. The editor thinks it is very practical, so share it with you as a reference and follow the editor to have a look.

Crypt

Well, we keep seeing crypt. Despite its different names, crypt is not a cellar or a burial pit for junk files, but a command to encrypt the contents of files. Now, crypt is usually implemented in a script that does its work by calling a binary file called mcrypt to simulate the previous crypt command. Using the mycrypt command directly is a better option.

Mcrypt xEnter the passphrase (maximum of 512 characters) Please use a combination of upper and lower case letters and numbers.Enter passphrase:Enter passphrase:File x was encrypted.

Note that the mcrypt command creates a second file with a .nc extension. It will not overwrite the file you are encrypting.

The mcrypt command has options for key size and encryption algorithm. You can also specify the key in the options, but this is not encouraged by the mcrypt command.

Kill

There are also kill commands-not murder, of course, but to end processes forcibly and non-forcibly, depending on the requirements to terminate them correctly. Of course, Linux is more than that. Instead, it has various kill commands to terminate the process. We have kill, pkill, killall, killpg, rfkill, skill () pronounced as es-kill), tgkill, tkill and xkill.

$killall runme [1] Terminated. / runme [2] Terminated. / runme [3]-Terminated. / runme [4] + Terminated. / runme

Shred

The Linux system also supports a command called shred. The shred command overwrites files to hide their previous contents and ensures that they cannot be recovered using the hard disk recovery tool. Keep in mind that the rm command basically removes the reference to the file in the directory file, but does not necessarily delete the content from disk or overwrite it. The shred command overwrites the contents of the file.

$shred dupes.txt$ more dupes.txt ▒ o A ▒▒ 9 ▒ lm ▒ o ▒ 1 '▒▒ f ▒ f ▒▒▒ I ▒▒ h ^} & ▒▒▒ {▒▒

Zombie

Although not a command, zombies are stubborn on Linux systems. Zombies are basically the remains of a death process that has not been completely cleaned up. Processes should not work like this-let death processes wander around, rather than simply let them die and enter digital paradise, so the existence of zombies shows that the process that left them here has some flaws.

An easy way to check if there are any zombie process leftovers on your system, look at the title line of the top command.

$toptop-18:50:38 up 6 days, 6:36, 2 users, load average: 0.00,0.00, 0.00Tasks: 171total, 1 running, 167sleeping, 0 stopped, 3 zombie `

< ==`%Cpu(s): 0.0 us, 0.0 sy, 0.0 ni, 99.9 id, 0.1 wa, 0.0 hi, 0.0 si, 0.0 stKiB Mem : 2003388 total, 250840 free, 545832 used, 1206716 buff/cacheKiB Swap: 9765884 total, 9765764 free, 120 used. 1156536 avail Mem 可怕！上面显示有三个僵尸进程。 at midnight 有时会在万圣节这么说，死者的灵魂从日落开始游荡直到午夜。Linux 可以通过 at midnight 命令跟踪它们的离开。用于安排在下次到达指定时间时运行的作业，at 的作用类似于一次性的 cron。 $ at midnightwarning: commands will be executed using /bin/shat>

Echo 'the spirits of the dead have left'at > job 3 at Thu Oct 31 00:00:00 2017

Daemon process

Linux systems are also highly dependent on daemons-processes that run in the background and provide many of the system's functions. The names of many daemons end with "d" This "d" represents the daemon daemon, indicating that the process has been running and supports some important functions. Some use the word "daemon".

$ps-ef | grep sshdroot 1142 10 Oct19? 00:00:00 / usr/sbin/sshd-Droot 25342 1142 0 18:34? 00:00:00 sshd: shs [priv] $ps-ef | grep daemon | grep-v grepmessage+ 790 10 Oct19? 00:00:01 / usr/bin/dbus-daemon-- system-- address=systemd:-- nofork-- nopidfile-- systemd-activationroot 836 10 Oct19? 00:00:02 / usr/lib/accountsservice/accounts-daemon Thank you for your reading! This is the end of the article on "sample Analysis of Linux commands for Halloween". I hope the above content can be helpful to you, so that you can learn more knowledge. if you think the article is good, you can share it for more people to see!

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