arsperger

Let suppose few things first
num = 55 Integer to perform bitwise operations (set, get, clear, toggle).
n = 4 0 based bit position to perform bitwise operations.

How to get a bit?
To get the nth bit of num right shift num, n times. Then perform bitwise AND & with 1.
bit = (num >> n) & 1;
How it works?

       0011 0111 (55 in decimal)

arsperger

Wireshark find SYN w/o SYNACK

• set display filter 'tcp.flags eq 0x02' (only SYN flag set)
• open Statistics -> Conversations
• Select the option "Limit to display filter"
• Select the tab TCP
• Sort the output by "Packets".

Those connections with 1 packet are likely the "good" connections (one SYN only)

arsperger

Troubleshoot TLS SIP traffic

HEP/EEP version 3 packets work only with sngrep 1.4.7 and above

cat <<EOF >> ~/.sngrep
set capture.device lo
set eep.listen on
set eep.listen.version 2
set eep.listen.address 127.0.0.1

arsperger

GDB commands by function - simple guide

Startup

% gdb  -help         	print startup help, show switches
% gdb object      	normal debug 
% gdb object core 	core debug (must specify core file)
%% gdb object pid  	attach to running process
% gdb  use file command to load object 

arsperger

// Makefile
// ${workspaceRoot} the path of the folder opened in VS Code
// ${file} the current opened file
// ${fileBasename} the current opened file's basename
// ${fileDirname} the current opened file's dirname
// ${fileExtname} the current opened file's extension
// ${cwd} the task runner's current working directory on startup
{
    "version": "0.1.0",
    "command": "bash",

arsperger

Vimdiff cheat sheet

git mergetool

In the middle file (future merged file), you can navigate between conflicts with ]c and [c.

Choose which version you want to keep with :diffget //2 or :diffget //3 (the //2 and //3 are unique identifiers for the target/master copy and the merge/branch copy file names).

:diffupdate (to remove leftover spacing issues)

:only (once you’re done reviewing all conflicts, this shows only the middle/merged file)

arsperger

tmux cheatsheet

As configured in my dotfiles.

start new:

tmux

start new with session name:

arsperger

## 1
# make git use SSH instead of HTTPS
git config --global url."git@gitlab.com:".insteadof="https://gitlab.com"

# or edit .gitconfig
[url "git@gitlab.com:"] insteadOf = https://gitlab.com

## 2
# in gitlab repo and create access tocken

arsperger

#!/bin/bash
IPT="/sbin/iptables"

# Server IP
SERVER_IP="$(ip addr show eth0 | grep 'inet ' | cut -f2 | awk '{ print $2}')"

# Your DNS servers you use: cat /etc/resolv.conf
DNS_SERVER="8.8.4.4 8.8.8.8"

# Allow connections to this package servers

arsperger

# jsonclient.py
# A simple JSONRPC client library, created to work with Go servers
# Written by Stephen Day
# Modified by Bruce Eckel to work with both Python 2 & 3
import json, socket, itertools, time
from datetime import datetime

class JSONClient(object):

    def __init__(self, addr, codec=json):