Posts on Rocasta Dot Com

The Adventure of the Engineer's Thumb — Story Guide

Tue, 07 Jul 2026 00:00:00 +0000

1. Story Guide

The original story runs approximately 6,000 words. For a 32-page picture book (13-14 double-page spreads after front matter), target text is ~600 words, roughly 40-50 words per spread.

This guide lists every spread with its scene, text, and the cats' involvement.

1.1. Page Credits

Pages 1-3: Front matter (half-title, title, copyright)
Pages 4-31: Story content (14 spreads)
Page 32: Back matter / colophon

2. Spread 1 — The Clock Strikes Seven

Page 4 — Full-page illustration

Bash Operator Cheatsheet

Wed, 26 Mar 2025 00:00:00 +0000

This cheat sheet covers Bash operators including file tests, string comparisons, logical operations, and arithmetic evaluations.

1. File Test Operators

File test operators check the status of files.

Operator Description Example

Operator	Description	Example
`-e`	File exists (any type)	`[[ -e file.txt ]]`
`-f`	File exists and is a regular file	`[[ -f script.sh ]]`
`-d`	File exists and is a directory	`[[ -d myfolder ]]`
`-r`	File is readable	`[[ -r data.txt ]]`
`-w`	File is writable	`[[ -w output.log ]]`
`-x`	File is executable	`[[ -x script.sh ]]`
`-s`	File exists and is not empty	`[[ -s nonempty.txt ]]`
`-L`	File is a symbolic link	`[[ -L shortcut ]]`
`-b`	File is a block device	`[[ -b /dev/sda1 ]]`
`-c`	File is a character device	`[[ -c /dev/ttyS0 ]]`
`-p`	File is a named pipe (FIFO)	`[[ -p pipefile ]]`
`-S`	File is a socket	`[[ -S /var/run/docker.sock ]]`

-e

File exists (any type)

[[ -e file.txt ]]

-f

File exists and is a regular file

[[ -f script.sh ]]

-d

File exists and is a directory

[[ -d myfolder ]]

-r

File is readable

[[ -r data.txt ]]

-w

File is writable

[[ -w output.log ]]

-x

File is executable

[[ -x script.sh ]]

-s

File exists and is not empty

[[ -s nonempty.txt ]]

-L

File is a symbolic link

[[ -L shortcut ]]

-b

File is a block device

[[ -b /dev/sda1 ]]

-c

File is a character device

[[ -c /dev/ttyS0 ]]

-p

File is a named pipe (FIFO)

[[ -p pipefile ]]

-S

File is a socket

[[ -S /var/run/docker.sock ]]

Diagnosing SMB Latency

Wed, 26 Mar 2025 00:00:00 +0000

1. Diagnosing the Problem

Check Network Speed
- Use iperf3 to measure network throughput between the two Macs.
  # On Mac B (SMB Server) iperf3 -s # On Mac A (Client) iperf3 -c <Mac B's IP>
- If the speed is close to 1Gbps, the network is performing as expected.
- If it’s significantly lower (e.g., below 500 Mbps), there may be a bottleneck in the network hardware or cabling.
Check Latency with ping
- Use ping to measure round-trip time between Mac A and Mac B.
  ping -c 10 <Mac B's IP>

Building a Gigabyte Brix SUSE Distro

Tue, 09 Jul 2024 00:00:00 +0000

Download the latest copy of SUSE tumbleweed
Burn this ISO image to thumb drive

dd if=<location_of_iso> of=/dev/rdisk<thumbdrive_disk_number> bs=1m

Put this in the front USB slot of the Brix
Power off and power on (a hard reboot is important)
Press the delete key repeatedly to get to Brix BIOS
Change boot order in boot section to specify USB drive as 1st boot
Save and Exit (reboot on thumb drive)
Run installer