Vim determines file types by extension to apply syntax highlighting and indentation. If you have custom file extensions that should be treated as C files, you need to configure Vim to recognize them. Using autocommand in .vimrc Add an autocommand to your ~/.vimrc: ” Treat .h and .c files in a custom directory as C…
Package managers on Debian and Ubuntu systems maintain detailed logs of all installations, upgrades, and removals. These logs are essential for auditing system changes, troubleshooting dependency issues, or understanding what was installed and when. Log File Locations The main log files you’ll work with are: /var/log/dpkg.log — Low-level package management operations logged by dpkg /var/log/apt/history.log…
Sometimes you need to view a file as it existed at a specific commit in Git — without checking out that commit or modifying your working directory. Git provides several ways to do this. View a File at a Specific Commit # View file content at a specific commit git show commit_hash:path/to/file # Example git…
Emacs doesn’t restore your cursor to the last editing position by default—Vim does this out of the box. Fortunately, save-place-mode is built into Emacs and requires minimal configuration to enable this behavior. Basic Setup Add this to your ~/.emacs.d/init.el: (save-place-mode 1) That’s all you need. The mode automatically saves your cursor position when you close…
Line wrapping in Vim controls whether long lines display across multiple visual lines or extend beyond the window edge. This is purely visual—wrapping doesn’t modify your file. Understanding when to enable, disable, and configure wrapping is essential for different workflows. Enable and Disable Wrapping Enable soft wrapping to see long lines across multiple rows: :set…
When you need to identify which package installed a command on your Fedora system, you have several reliable methods depending on whether the package is already installed. Quick lookup for installed commands The fastest approach combines which to locate the command with rpm to query the owning package: $ rpm -qf $(which ping) iputils-8.40-4.fc40.x86_64 The…
Line number displays in Emacs can feel cramped without proper spacing. Modern Emacs provides built-in control over line number formatting and width—no external packages needed. Using display-line-numbers-mode display-line-numbers-mode is the standard in Emacs 25+ and should be your default choice. It’s faster and more maintainable than the older linum-mode. Enable it globally: (global-display-line-numbers-mode t) To…
Thunderbird stores message filters in per-account configuration files, making it inconvenient to replicate filters across multiple accounts or installations. Rather than recreating filters manually, you can copy filter files directly or use symbolic links to keep filters synchronized. Where Thunderbird Stores Filters Thunderbird saves filter rules in msgFilterRules.dat, a plain text configuration file. Each account…
When you run crontab -e, git commit, visudo, or similar commands, Linux applications need to know which text editor to launch. This is controlled by environment variables and system configuration, with several methods available depending on your needs. Understanding EDITOR and VISUAL The EDITOR environment variable tells applications which text editor to use. A related…
Vim’s default OCaml indentation is limited and doesn’t handle the language’s syntax well. You’ll want to use ocp-indent, a dedicated indentation tool built specifically for OCaml that understands the language’s scoping and structure rules. Installing ocp-indent First, install the tool via OPAM (OCaml Package Manager): opam install ocp-indent If you don’t have OPAM installed, install…
Setting environment variables in Bash is one of the most fundamental skills for working with Linux command lines and shell scripts. Bash provides several ways to define and manage variables. Setting a Variable for the Current Shell MY_VAR=”hello world” Important: No spaces around the = sign. MY_VAR = “value” will produce an error because Bash…
[md] Use setenv to set an environment variable in csh: setenv VARIABLE value Replace VARIABLE with the name of the variable and value with its value. The variable is immediately available in the current shell and inherited by child processes. ## Examples Set a simple variable: setenv PATH /usr/local/bin:/usr/bin:/bin setenv EDITOR vim setenv JAVA_HOME /usr/lib/jvm/java-17-openjdk…
[md] When you install Core via opam, the interface files (.mli) are stored in your OPAM switch directory. The exact path depends on your OCaml version and OPAM setup. ## Standard Location The .mli files for Core are located at: ~/.opam/$(ocaml -version | awk ‘{print $NF}’)/lib/core/ where the OCaml version is part of the switch…
Vim’s regex engine is powerful but requires understanding its syntax rules, which differ significantly from standard POSIX extended regex. Whether you’re doing basic substitutions or complex text transformations, knowing how Vim handles regex patterns will save you hours of frustration. Vim Regex Basics Vim supports multiple regex engines, controlled by the magic setting. By default,…
The default OCaml toplevel lacks basic readline features like history, line editing, and command completion. Here are the practical approaches to fix this. utop: Full-Featured Replacement The best option for daily interactive OCaml work is utop, a replacement toplevel that provides: Syntax highlighting with color output Command completion (for identifiers, keywords, library functions) Parenthesis and…
You have two branches with diverging histories and need to apply only certain commits from one branch to another. Git’s cherry-pick command lets you do exactly that. The scenario Say you have: dev branch: c0 → c1 → c2 → c3 → c4 master branch: c0 → c5 → c6 Commits c2 and c3 fix…
Vim ships with built-in completion that many people don’t fully leverage. Before reaching for plugins, understand what’s already available: Ctrl+N / Ctrl+P: Basic keyword completion from open buffers and loaded files Ctrl+X Ctrl+F: Filename completion Ctrl+X Ctrl+]: Tag completion (requires ctags) Ctrl+X Ctrl+O: Omnicompletion (language-aware, when available) The omnicompletion (Ctrl+X Ctrl+O) is what resembles IDE…
The default Vim plugin directory structure under ~/.vim is inherently messy. Without a plugin manager, files from different plugins scatter across autoload/, plugin/, ftplugin/, colors/, and other directories, making it difficult to track which files belong to which plugin. Removing a plugin requires manually hunting down and deleting its files across multiple locations. Several plugin…
By default, Vim searches case sensitively. You can match dog, Dog, DOG, and other case variations using one of three approaches. Using the ignorecase Option The simplest method is to enable the ignorecase setting: :set ignorecase Now /dog will match dog, Dog, DOg, and any other case variation. To disable it: :set noignorecase Add this…
Vim performs case-sensitive searches by default. If you search for error, it won’t match Error or ERROR. Here are several ways to enable case-insensitive searching. Toggle Case Sensitivity During Search The quickest method — append \c anywhere in your search pattern: /error\c This matches error, Error, ERROR, and any other casing. The \c flag applies…