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Jimmy Sawczuk jimmysawczuk

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@Tamal
Tamal / set-chroot.sh
Last active October 26, 2025 15:12
Setting up chroot from a live image in Fedora. Regenerate grub2 for Fedora.
$ # Use Live CD to boot
$ sudo su # Switch to root
$ fdisk -l # Get names of root, boot & EFI partition names. you can also use blkid
$ mount /dev/mapper/fedora_localhost--live-root /mnt # mount root partition
$ cat /mnt/etc/fedora-release
Fedora release 31 (Thirty One)
$ mount /dev/nvme0n1p2 /mnt/boot # mount boot partition
$ mount /dev/nvme0n1p1 /mnt/boot/efi # mount EFI partition
# Note: If you are not able to mount EFI partition ('Input/Output error'),
# You may have to repair ESP file system or format ESP.
@ianfoo
ianfoo / git-diff-branch-only.sh
Created September 21, 2019 00:24
Shell function to show git diff only for changes made to a branch
git-diff-branch-only () {
local branch=${1:-$(git branch --show-current)}
local base=${2:-master}
git diff $(git merge-base $branch $base) $branch
}
@lfender6445
lfender6445 / gist:9919357
Last active October 8, 2025 09:24
Pry Cheat Sheet

Pry Cheat Sheet

Command Line

  • pry -r ./config/app_init_file.rb - load your app into a pry session (look at the file loaded by config.ru)
  • pry -r ./config/environment.rb - load your rails into a pry session

Debugger

@piscisaureus
piscisaureus / pr.md
Created August 13, 2012 16:12
Checkout github pull requests locally

Locate the section for your github remote in the .git/config file. It looks like this:

[remote "origin"]
	fetch = +refs/heads/*:refs/remotes/origin/*
	url = [email protected]:joyent/node.git

Now add the line fetch = +refs/pull/*/head:refs/remotes/origin/pr/* to this section. Obviously, change the github url to match your project's URL. It ends up looking like this:

@josephwecker
josephwecker / new_bashrc.sh
Created August 11, 2012 04:36
Replace .bashrc, .bash_profile, .profile, etc. with something much more clean, consistent, and meaningful. Now a repo: https://github.com/josephwecker/bashrc_dispatch
#!/bin/bash
# License: Public Domain.
# Author: Joseph Wecker, 2012
#
# -- DEPRICATED --
# This gist is slow and is missing .bashrc_once
# Use the one in the repo instead! https://github.com/josephwecker/bashrc_dispatch
# (Thanks gioele)
#
# Are you tired of trying to remember what .bashrc does vs .bash_profile vs .profile?
@jboner
jboner / latency.txt
Last active October 31, 2025 03:43
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD
@psebborn
psebborn / countCSSRules.js
Last active April 25, 2023 11:43
Count the number of rules and selectors for CSS files on the page. Flags up the >4096 threshold that confuses IE
function countCSSRules() {
var results = '',
log = '';
if (!document.styleSheets) {
return;
}
for (var i = 0; i < document.styleSheets.length; i++) {
countSheet(document.styleSheets[i]);
}
function countSheet(sheet) {
@dave1010
dave1010 / htaccess
Created December 14, 2011 13:07
HTTP Status Cats Apache (htaccess) config
# HTTP Status Cats
# Apache (htaccess) config created by @dave1010
# Licensed CC BY 2.0
# Images CC BY 2.0, from GirlieMac's photostream:
# http://www.flickr.com/photos/girliemac/sets/72157628409467125/with/6508023065/
# Usage: copy save this file as .htaccess or add it to your httpd.conf
ErrorDocument 404 '<a href="http://www.flickr.com/photos/girliemac/6508022985/" title="404 - Not Found by GirlieMac, on Flickr"><img src="http://farm8.staticflickr.com/7172/6508022985_b22200ced0.jpg" width="500" height="400" alt="404 - Not Found"></a>'