Tutorials and howtos on git configuration and usage.
If you’ve pushed a commit with a bad message, you can fix it—but the approach depends on whether others have pulled that commit yet. When Rewriting Is Safe Only amend and force-push if: You’re the only one using the repository You’re absolutely certain no one else has pulled the commit yet Your branch protection rules…
Emacs handles line ending conversions through its buffer coding system. Whether you’re converting CRLF (DOS/Windows) to LF (Unix) or the reverse, the process is straightforward. DOS to Unix (CRLF to LF) Open the file in Emacs and run: M-x set-buffer-file-coding-system RET undecided-unix Or use the keyboard shortcut: C-x RET f undecided-unix Then save the file:…
The simplest way to see your commit history as a tree structure: git log –graph –oneline This produces a text-based graph showing branch relationships and merges with abbreviated commit hashes: * b5dc8b9 Merge branch ‘main’ into develop |\ | * 7514ef1 revised the README.md | * 6692428 align size to page for both shalloc and…
Bash provides comparison operators for conditionals through the test command (aliased as [), the [[ ]] compound command, and the (( )) arithmetic command. Each has specific use cases and behavior differences worth understanding. String Comparisons String comparisons work with test/[ and [[ ]]: Operator Meaning -n STRING String length is nonzero (true if not…
The built-in etags command doesn’t recursively traverse directories by default, but generating TAGS files across your entire project is straightforward with the right tools and setup. Using ctags (Recommended) The simplest approach is ctags with the -e flag, which generates Emacs-compatible TAGS files: ctags -e -R . The -R flag enables recursive traversal. This works…
Emacs startup time matters when you’re opening files frequently from the command line or in scripts. A few targeted optimizations can reduce perceived startup overhead from seconds to near-instant. Run Emacs as a daemon with emacsclient The most effective optimization is the server/client architecture. Start Emacs once as a daemon, then reuse that instance for…
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…
The TP-Link TL-WN725N v2 uses the Realtek RTL8188EU chipset. While kernel support has improved significantly, you may still need to compile drivers manually on recent Fedora releases. Check current driver status First, verify whether your adapter is recognized: lsusb | grep -i realtek If nothing appears, the driver isn’t loaded. Check if the kernel module…
Sharing a router with roommates means dealing with bandwidth conflicts. When someone’s running torrent clients, streaming, or other bandwidth-intensive applications without limits, everyone else suffers. Here’s how to handle it systematically. Start with conversation Before implementing technical controls, talk to your roommates. Most P2P and download applications have built-in rate limiting. Asking someone to cap…
Finding large files is something you end up doing a lot — disk fills up, you need to track down what’s eating space, or you’re auditing a directory before archiving. The find command handles this cleanly. Basic usage Find all files larger than 500MB under the current directory: find . -type f -size +500M The…
When a disk fills up or you’re doing a cleanup pass, finding the biggest files quickly saves a lot of time. Here are the practical approaches on Linux. Top 10 largest files in the current directory du -ah –max-depth=1 | sort -rh | head -n 10 Breaking this down: du -ah shows sizes for all…
A4-sized PDFs—particularly technical papers and academic documents—render poorly on Kindle devices. The small fonts become nearly unreadable, and Amazon’s “Send to Kindle” feature often destroys formatting in the process. You need a tool designed specifically for this workflow. Why Standard Conversion Fails Amazon’s email-to-Kindle conversion assumes reflowable text content. Technical papers with multi-column layouts, equations,…
You’ve accidentally broken a file and need to restore it from an earlier commit without touching anything else in your repository. Here’s how. Restore a file to a specific commit To restore my_file.name to its state at a specific commit: git checkout commit_sha1 my_file.name Replace commit_sha1 with the actual commit hash. You can find it…
When you work with multiple git servers or need different credentials for different hosts, SSH’s config file lets you specify which key to use for each server. This is cleaner than managing aliases or environment variables. Setting Up ~/.ssh/config Create or edit ~/.ssh/config and add entries for each server: Host git.example.org Port 22111 IdentityFile ~/.ssh/id_rsa.git.example.org…
Trailing spaces and tabs at the end of lines are common annoyances in source code and configuration files. They’re invisible, waste space, and can cause issues with certain tools or version control systems. Here’s how to remove them efficiently. Using sed The most straightforward approach with sed: sed ‘s/[[:space:]]*$//’ your_file > your_file.tmp && mv your_file.tmp…
SSH is essential for serious shared hosting management — it beats FTP by a mile and gives you real shell access for development, deployment, and automation. Most reputable shared hosting providers support SSH, though availability and implementation vary. Major Providers with SSH Support DreamHost DreamHost has long supported SSH on shared hosting. You’ll need to…
The Jane Street OPAM repository contains specialized OCaml packages and libraries maintained by Jane Street, including their popular Core library and related tools. You’ll need to add this repository to your OPAM configuration to access these packages. Method 1: Clone and Add Locally If you prefer to clone the repository first and add it as…
WordPress Twenty Thirteen theme shows full post content on archive pages by default. Using excerpts instead keeps archive pages clean and improves page load speed by showing just a summary of each post. Enable Excerpts on Archive Pages Add this to your theme’s functions.php or a custom plugin: function twentythirteen_excerpts_on_archives($content) { if (is_archive() || is_home())…
Question2Answer’s RSS feed configuration includes a toggle for “Include full text in feeds” but offers no built-in option to display excerpts instead of full content. If you need excerpt functionality, you’ll need to modify the feed generation code. This approach works with Question2Answer 1.5.4+. The method involves creating a custom feed handler that truncates content…
Local branches List all branches on your local repository: git branch This shows only branches that exist locally on your machine. Remote branches To list all branches on the remote server, use the -r flag: git branch -r This displays remote-tracking branches — local references to branches that exist on the remote repository. These are…