Setting up Java on Linux means choosing the installation directory a program should use. JAVA_HOME is an environment variable that names that Java installation directory. I’ll show you how to find the JDK root and set JAVA_HOME for the shell or system that runs your program. TL;DR: Set JAVA_HOME to the JDK directory Set JAVA_HOME
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Sometimes a program keeps running after its work is done, and you need to stop it without looking up a process ID. The PSmisc version of killall selects running programs by command name and sends them a signal, with SIGTERM as its default. In this piece, I’ll show you how to check your installed implementation
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Managing a Debian or Ubuntu server from a browser calls for an administration tool that runs on the server. Webmin provides that interface, which you access through a browser. I’ll show how to install Webmin from its APT repository and connect to its HTTPS interface. TL;DR Use Webmin’s setup script to configure its APT repository
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Linux password rules can be stored in different places, depending on whether they check a new password or control when an account password expires. A Linux password policy combines password-quality checks with account settings that determine when passwords expire. I’ll show how to inspect the active PAM password stack and read an account’s aging settings
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Running a Java program requires a runtime, while building one also requires a compiler. Debian provides OpenJDK packages through APT, including a runtime and a development kit. This article shows how to check which Java packages your Debian repositories offer and choose the JDK or runtime package to install. TL;DR Install Debian’s default Java development
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At the prompt, a script may receive a value typed by the user or capture output from a command. A shell variable gives that value a name the script can use later. In this piece, I’ll show how to assign and use Bash variables, including passing a value to a child process. TL;DR In Bash,
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Working with text records at the shell can mean finding the rows and fields that matter. awk reads text records and lets you select fields or calculate totals. I’ll show how to select fields and summarize matching records, then save the program in an awk file for reuse. TL;DR: Use awk to select and reshape
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To see which login sessions a Linux system has recorded, use the who command. It reads login records, usually from utmp, and lists the sessions they contain. I’ll explain its output fields and show how to select the session associated with standard input. TL;DR The who command lists login sessions recorded on a Linux system,
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When a file or directory needs different access, the task is to change its permissions without opening it up more than intended. chmod changes the rules that control access to files and directories. I’ll show how to set permissions with a number such as 640 or a letter-based change such as u+x, then check the
Linux chmod Command: Change File Permissions Read More »
Terminal output can be useful to review alongside the commands that produced it. The Linux script command records an interactive terminal session in a file called a typescript, which contains entered commands and visible results. I’ll show you how to record and replay a session, and how to check its log for private input. TL;DR:
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