search

What does $ mean in linux

Nov 04, 2019 am 10:22 AM
linux

$What does it mean in linux?

The $ in linux is the "command prompt" where you can enter commands at the end. The current user may be prompted in front of the command prompt. Some information, under Linux, the user will be prompted for the current directory and current user.

Recommended: Linux Tutorial

What does $ mean in linux

##$ is used to give variable commands in Linux, for example $JAVA_HOME refers to the environment variable of JAVA_HOME.

echo $JAVA_HOME can output the home directory of jdk in the Linux terminal.

$ is also used when passing parameters to the script in the Shell script. For example, the format for obtaining parameters in the script is: $n, n represents a number, 1 is the first parameter to execute the script, and 2 is the execution The second parameter of the script, and so on.

Linux is a set of Unix-like operating systems that are free to use and freely disseminated. It is a multi-user, multi-task, multi-threading and multi-CPU operating system based on POSIX and Unix. It can run major Unix software tools, applications and network protocols. It supports 32-bit and 64-bit hardware. Linux inherits the network-centric design philosophy of Unix and is a multi-user network operating system with stable performance.

The above is the detailed content of What does $ mean in linux. For more information, please follow other related articles on the PHP Chinese website!

Statement
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
How Debian improves Hadoop data processing speedHow Debian improves Hadoop data processing speedApr 13, 2025 am 11:54 AM

This article discusses how to improve Hadoop data processing efficiency on Debian systems. Optimization strategies cover hardware upgrades, operating system parameter adjustments, Hadoop configuration modifications, and the use of efficient algorithms and tools. 1. Hardware resource strengthening ensures that all nodes have consistent hardware configurations, especially paying attention to CPU, memory and network equipment performance. Choosing high-performance hardware components is essential to improve overall processing speed. 2. Operating system tunes file descriptors and network connections: Modify the /etc/security/limits.conf file to increase the upper limit of file descriptors and network connections allowed to be opened at the same time by the system. JVM parameter adjustment: Adjust in hadoop-env.sh file

How to learn Debian syslogHow to learn Debian syslogApr 13, 2025 am 11:51 AM

This guide will guide you to learn how to use Syslog in Debian systems. Syslog is a key service in Linux systems for logging system and application log messages. It helps administrators monitor and analyze system activity to quickly identify and resolve problems. 1. Basic knowledge of Syslog The core functions of Syslog include: centrally collecting and managing log messages; supporting multiple log output formats and target locations (such as files or networks); providing real-time log viewing and filtering functions. 2. Install and configure Syslog (using Rsyslog) The Debian system uses Rsyslog by default. You can install it with the following command: sudoaptupdatesud

How to choose Hadoop version in DebianHow to choose Hadoop version in DebianApr 13, 2025 am 11:48 AM

When choosing a Hadoop version suitable for Debian system, the following key factors need to be considered: 1. Stability and long-term support: For users who pursue stability and security, it is recommended to choose a Debian stable version, such as Debian11 (Bullseye). This version has been fully tested and has a support cycle of up to five years, which can ensure the stable operation of the system. 2. Package update speed: If you need to use the latest Hadoop features and features, you can consider Debian's unstable version (Sid). However, it should be noted that unstable versions may have compatibility issues and stability risks. 3. Community support and resources: Debian has huge community support, which can provide rich documentation and

TigerVNC share file method on DebianTigerVNC share file method on DebianApr 13, 2025 am 11:45 AM

This article describes how to use TigerVNC to share files on Debian systems. You need to install the TigerVNC server first and then configure it. 1. Install the TigerVNC server and open the terminal. Update the software package list: sudoaptupdate to install TigerVNC server: sudoaptinstalltigervnc-standalone-servertigervnc-common 2. Configure TigerVNC server to set VNC server password: vncpasswd Start VNC server: vncserver:1-localhostno

Debian mail server firewall configuration tipsDebian mail server firewall configuration tipsApr 13, 2025 am 11:42 AM

Configuring a Debian mail server's firewall is an important step in ensuring server security. The following are several commonly used firewall configuration methods, including the use of iptables and firewalld. Use iptables to configure firewall to install iptables (if not already installed): sudoapt-getupdatesudoapt-getinstalliptablesView current iptables rules: sudoiptables-L configuration

Debian mail server SSL certificate installation methodDebian mail server SSL certificate installation methodApr 13, 2025 am 11:39 AM

The steps to install an SSL certificate on the Debian mail server are as follows: 1. Install the OpenSSL toolkit First, make sure that the OpenSSL toolkit is already installed on your system. If not installed, you can use the following command to install: sudoapt-getupdatesudoapt-getinstallopenssl2. Generate private key and certificate request Next, use OpenSSL to generate a 2048-bit RSA private key and a certificate request (CSR): openss

Debian mail server virtual host configuration methodDebian mail server virtual host configuration methodApr 13, 2025 am 11:36 AM

Configuring a virtual host for mail servers on a Debian system usually involves installing and configuring mail server software (such as Postfix, Exim, etc.) rather than Apache HTTPServer, because Apache is mainly used for web server functions. The following are the basic steps for configuring a mail server virtual host: Install Postfix Mail Server Update System Package: sudoaptupdatesudoaptupgrade Install Postfix: sudoapt

Debian Mail Server DNS Setup GuideDebian Mail Server DNS Setup GuideApr 13, 2025 am 11:33 AM

To configure the DNS settings for the Debian mail server, you can follow these steps: Open the network configuration file: Use a text editor (such as vi or nano) to open the network configuration file /etc/network/interfaces. sudonano/etc/network/interfaces Find network interface configuration: Find the network interface to be modified in the configuration file. Normally, the configuration of the Ethernet interface is located in the ifeth0 block.

See all articles

Hot AI Tools

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.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

AI Hentai Generator

AI Hentai Generator

Generate AI Hentai for free.

Hot Article

R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)
3 weeks agoBy尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. Best Graphic Settings
3 weeks agoBy尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. How to Fix Audio if You Can't Hear Anyone
3 weeks agoBy尊渡假赌尊渡假赌尊渡假赌
WWE 2K25: How To Unlock Everything In MyRise
4 weeks agoBy尊渡假赌尊渡假赌尊渡假赌

Hot Tools

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

mPDF

mPDF

mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),

DVWA

DVWA

Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software

Dreamweaver Mac version

Dreamweaver Mac version

Visual web development tools

SecLists

SecLists

SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.