亚洲国产日韩欧美一区二区三区,精品亚洲国产成人av在线,国产99视频精品免视看7,99国产精品久久久久久久成人热,欧美日韩亚洲国产综合乱

Home System Tutorial LINUX How to hide your Linux command line history

How to hide your Linux command line history

Aug 17, 2024 am 07:34 AM
linux linux tutorial Red Hat linux system linux command linux certification red hat linux linux video

If you are a Linux command line user, sometimes you may not want certain commands to be recorded in your command line history. There could be many reasons, for example, you hold a certain position in a company and you have certain privileges that you don't want others to abuse. Or maybe there are some particularly important commands that you don't want to execute by mistake while browsing the history list.

However, is there a way to control which commands go into the history list and which don't? Or in other words, can we enable incognito mode like a browser in a Linux terminal? The answer is yes, and depending on the specific goals you want, there are many ways to achieve it. In this article, we’ll discuss some proven methods.

Note: All commands appearing in this article have been tested under Ubuntu.

Different possible methods

The first two methods have been described in a previous article. If you already know this, you can skip this part. However, if you don't understand it, it is recommended to read it carefully.

1. Insert a space before the command

Yes, you read that right. By inserting a space before the command, the command will be ignored by the shell, which means it will not appear in the history. But this method has a prerequisite. It will only work if your environment variable HISTCONTROL is set to "ignorespace" or "ignoreboth". In most cases, this is the default value.

So, like the following command (here [space] means entering a space):

[space]echo "this is a top secret"

If you have previously executed the following command to set environment variables, the above command will not appear in the history.

export HISTCONTROL = ignorespace

The screenshot below is an example of this approach.

如何隱藏你的 Linux 的命令行歷史

The fourth "echo" command is not recorded in the history because there is a space in front of it.

2. Disable all history of the current session

If you want to disable all history for a session, you can simply clear the value of the environment variable HISTSIZE before starting command line work. Execute the following command to clear its value:

export HISTSIZE=0

HISTSIZE indicates the number of commands (number of lines) that can be saved in the history list of a bash session. By default it is set to a non-zero value, for example on my computer it is 1000.

So the above mentioned command sets its value to 0, with the result that nothing will be stored in the history until you close the terminal. Remember that you also cannot see previously executed commands by pressing the up arrow key or running the history command.

3. Clear the entire history after finishing the work

This can be seen as another implementation of the solution proposed in the previous part. The only difference is to execute this command after you have finished all your work. The following is the command just mentioned:

history -cw

As mentioned just now, this has the same effect as the HISTSIZE method.

4. Turn off history only for your work

While the previously described methods (2 and 3) will serve the purpose, they can clear the entire history, and in many cases some may not be what we expect. Sometimes you may want to save the history until you started working on the command line. For such needs, you start executing the following commands before working:

[space]set +o history

Note: [space] means space. And because of the spaces, the command itself is not logged either.

The above command will temporarily disable the history function, which means that all operations you perform after this command will not be recorded in the history, but everything before this command will be recorded in the history list as is.

To re-enable the history function, execute the following command:

[Space]set -o history

It will restore the environment to its original state, that is, you have completed your work, and the commands after executing the above command will appear in the history.

5. Delete the specified command from the history

現(xiàn)在假設(shè)歷史記錄中已經(jīng)包含了一些你不希望記錄的命令。這種情況下我們?cè)趺崔k?很簡(jiǎn)單。直接動(dòng)手刪除它們。通過下面的命令來刪除:

history | grep "part of command you want to remove"

上面的命令會(huì)輸出歷史記錄中匹配的命令,每一條前面會(huì)有個(gè)數(shù)字。

一旦你找到你想刪除的命令,執(zhí)行下面的命令,從歷史記錄中刪除那個(gè)指定的項(xiàng):

history -d [num]

下面是這個(gè)例子的截圖。

如何隱藏你的 Linux 的命令行歷史

第二個(gè) ‘echo’命令被成功的刪除了。

(如果你不希望上述命令本身也被記錄進(jìn)歷史中,你可以在上述命令前加個(gè)空格)

同樣的,你可以使用向上的箭頭一直往回翻看歷史記錄。當(dāng)你發(fā)現(xiàn)你感興趣的命令出現(xiàn)在終端上時(shí),按下 “Ctrl + U”清除整行,也會(huì)從歷史記錄中刪除它。

總結(jié)

有多種不同的方法可以操作 Linux 命令行歷史來滿足你的需求。然而請(qǐng)記住,從歷史中隱藏或者刪除命令通常不是一個(gè)好習(xí)慣,盡管本質(zhì)上這并沒有錯(cuò)。但是你必須知道你在做什么,以及可能產(chǎn)生的后果。

The above is the detailed content of How to hide your Linux command line history. For more information, please follow other related articles on the PHP Chinese website!

Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undress AI Tool

Undress AI Tool

Undress images for free

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Hot Topics

PHP Tutorial
1488
72
How does the cost of ownership differ between Linux and Windows? How does the cost of ownership differ between Linux and Windows? Jun 09, 2025 am 12:17 AM

Linux's cost of ownership is usually lower than Windows. 1) Linux does not require license fees, saving a lot of costs, while Windows requires purchasing a license. 2) Linux has low hardware requirements and can extend the service life of the device. 3) The Linux community provides free support to reduce maintenance costs. 4) Linux is highly secure and reduces productivity losses. 5) The Linux learning curve is steep, but Windows is easier to use. The choice should be based on specific needs and budget.

What Are the Prerequisites for Installing Redis on Linux? What Are the Prerequisites for Installing Redis on Linux? Jun 10, 2025 am 12:02 AM

Installing RedisonLinux requires the following prerequisites: 1. A Linux distribution, such as Ubuntu, CentOS, or Debian; 2. GCC compiler, used to compile Redis from source; 3. Make and libc6-dev, used to build Redis; 4. Tcl (optional), used to run Redis tests. These tools ensure smooth installation and testing of Redis.

How to install Linux alongside Windows (dual boot)? How to install Linux alongside Windows (dual boot)? Jun 18, 2025 am 12:19 AM

The key to installing dual systems in Linux and Windows is partitioning and boot settings. 1. Preparation includes backing up data and compressing existing partitions to make space; 2. Use Ventoy or Rufus to make Linux boot USB disk, recommend Ubuntu; 3. Select "Coexist with other systems" or manually partition during installation (/at least 20GB, /home remaining space, swap optional); 4. Check the installation of third-party drivers to avoid hardware problems; 5. If you do not enter the Grub boot menu after installation, you can use boot-repair to repair the boot or adjust the BIOS startup sequence. As long as the steps are clear and the operation is done properly, the whole process is not complicated.

What Are the Steps to Install Redis on a Linux System? What Are the Steps to Install Redis on a Linux System? Jun 11, 2025 am 12:11 AM

ToinstallRedisonaLinuxsystem,followthesesteps:1)DownloadandextractRedisfromtheofficialGitHubrepository,2)CompileRedisusingthe'make'command,3)InstallRediswith'sudomakeinstall',4)ConfigureRedisbycopyingandeditingtheconfigurationfile,and5)StartRedisusin

How to enable the EPEL (Extra Packages for Enterprise Linux) repository? How to enable the EPEL (Extra Packages for Enterprise Linux) repository? Jun 17, 2025 am 09:15 AM

The key to enabling EPEL repository is to select the correct installation method according to the system version. First, confirm the system type and version, and use the command cat/etc/os-release to obtain information; second, enable EPEL through dnfinstallepel-release on CentOS/RockyLinux, and the 8 and 9 version commands are the same; third, you need to manually download the corresponding version of the .repo file and install it on RHEL; fourth, you can re-import the GPG key when encountering problems. Note that the old version may not be supported, and you can also consider enabling epel-next to obtain the test package. After completing the above steps, use dnfrepolist to verify that the EPEL repository is successfully added.

How does Linux perform compared to Windows for web server workloads? How does Linux perform compared to Windows for web server workloads? Jun 08, 2025 am 12:18 AM

Linux usually performs better in web server performance, mainly due to its advantages in kernel optimization, resource management and open source ecosystem. 1) After years of optimization of the Linux kernel, mechanisms such as epoll and kqueue make it more efficient in handling high concurrent requests. 2) Linux provides fine-grained resource management tools such as cgroups. 3) The open source community continuously optimizes Linux performance, and many high-performance web servers such as Nginx are developed on Linux. By contrast, Windows performs well when handling ASP.NET applications and provides better development tools and commercial support.

How to choose a Linux distro for a beginner? How to choose a Linux distro for a beginner? Jun 19, 2025 am 12:09 AM

Newbie users should first clarify their usage requirements when choosing a Linux distribution. 1. Choose Ubuntu or LinuxMint for daily use; programming and development are suitable for Manjaro or Fedora; use Lubuntu and other lightweight systems for old devices; recommend CentOSStream or Debian to learn the underlying principles. 2. Stability is preferred for UbuntuLTS or Debian; you can choose Arch or Manjaro to pursue new features. 3. In terms of community support, Ubuntu and LinuxMint are rich in resources, and Arch documents are technically oriented. 4. In terms of installation difficulty, Ubuntu and LinuxMint are relatively simple, and Arch is suitable for those with basic needs. It is recommended to try it first and then decide.

How to add a new disk to Linux How to add a new disk to Linux Jun 27, 2025 am 12:15 AM

The steps to add a new hard disk to the Linux system are as follows: 1. Confirm that the hard disk is recognized and use lsblk or fdisk-l to check; 2. Use fdisk or parted partitions, such as fdisk/dev/sdb and create and save; 3. Format the partition to a file system, such as mkfs.ext4/dev/sdb1; 4. Use the mount command for temporary mounts, such as mount/dev/sdb1/mnt/data; 5. Modify /etc/fstab to achieve automatic mount on the computer, and test the mount first to ensure correctness. Be sure to confirm data security before operation to avoid hardware connection problems.

See all articles