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Why I use `node`, `deno`, `bun`, `qjs`, `tjs` at the same time.

Winds up being a (not the) rather comprehensive JavaScript toolbox. The idea being for the modern JavaScript programmer can use all of the tools available for a given requirement, task or job, without preference for any. No external bundlers or compilers are needed. No frameworks are needed. I can use qjs or tjs for systems with minimal RAM and disk space; and when I want to use Web API's deno makes an effort to provide those interfaces. In some cases I can run the exact same code in bun, deno, and node, which provides a means to perform 1:1 testing as to performance.

There's probably a few things I am unintentionally omitting below. These are just a brief synposis. I'll update accordingly.

`vs` Questions

http://stackoverflow.com/questions/804115 (rebase vs merge).
https://www.atlassian.com/git/tutorials/merging-vs-rebasing (rebase vs merge)
https://www.atlassian.com/git/tutorials/undoing-changes/ (reset vs checkout vs revert)
http://stackoverflow.com/questions/2221658 (HEAD^ vs HEAD~) (See git rev-parse)
http://stackoverflow.com/questions/292357 (pull vs fetch)
http://stackoverflow.com/questions/39651 (stash vs branch)
http://stackoverflow.com/questions/8358035 (reset vs checkout vs revert)

How to grep the output of tail

When following a log file with the tail command you are typically looking for a specific pattern. If the log output is verbous it can be difficult to catch the lines your interested in. For example a PHP log file might contain many PHP Notice: entries but your only interested in lines containing PHP Fatal error:. To grep the output of tail simply tell the grep command to red from stdin and pipe the output from tail to grep as follows.

tail -f {path/to/log/file} | grep 'PHP Fatal error:' -

How to set up PulseAudio over Network

PulseAudio actually has great networking capabilities. Especially when combined with Avahi/Zeroconf it is especially easy to set up, though technically it should also be possible without.

Setting up the server

Open /etc/pulseaudio/default.pa
At the end of the file, add load-module module-native-protocol-tcp auth-ip-acl=127.0.0.1;192.168.254.0/24 auth-anonymous=1 to activate networked audio from 192.168.254.0-255 without needing authentication.
Kill pulseaudio, it should be auto-restarted, or restart your login session to activate the changes. You should now be able to set PULSE_SERVER=192.168.254.XXX and have the remote audio working! If not check the firewall settings, PulseAudio seems to open a random port by default.

Setting up automatic configuration and discovery

On both the server and client, install pulseaudio-module-zeroconf and avahi, then after installing make sure Avahi always runs by running systemctl enable --now avahi-daemon

scph5500.bin 26-Aug-2018 20:47 512.0K

scph5501.bin 26-Aug-2018 20:47 512.0K

scph5502.bin 26-Aug-2018 20:47 512.0K

Configuring Cyclone DDS for Wifi + Ethernet connection on an Enterprise Network (for ROS2)

For communication between wifi and ethernet devices, the DDS layer in ROS2 relies on the multicast ability of a given network.

This is often disabled on enterprise networks (at university or work etc) for (I think) security reasons .

To get around this, you have to configure CycloneDDS to comunicate in a unicast manner, and you must specify the local IPs of all the participants you want to communicate.

_I am using CycloneDDS instead of the default (for ROS2 humble at least) FastDDS, because I ran into lots of issues trying to get topic

	import os


	def parse_man_file(man_filepath):
	with open(man_filepath, "r") as man_file:
	lines = man_file.read().split("\n")

	formatted_lines = []
	for line in lines:
	# remove Apple developer comments included on the same line and strip off trailing white space

	# alias to edit commit messages without using rebase interactive
	# example: git reword commithash message
	reword = "!f() {\n GIT_SEQUENCE_EDITOR=\"sed -i 1s/^pick/reword/\" GIT_EDITOR=\"printf \\\"%s\\n\\\" \\\"$2\\\" >\" git rebase -i \"$1^\";\n git push -f;\n}; f"

	# edit all commit messages
	git rebase -i --root

	# clone all your repos with gh cli tool
	gh repo list --json name -q '.[].name' \| xargs -n1 gh repo clone

	package main
	import "fmt"
	func main() {
	fmt.Println("hello world")
	}