Dell Latitude 5501 Linux Deep Sleep Experiment
Published:
I tried to reduce suspend battery drain on my Dell Latitude 5501 running Ubuntu 24.04.
Posts by Tags
acpi
address
BLE Random Address Type Bits
Published:
BLE random device addresses encode their address type in the two most significant bits of the random address.
agents
Good Software Rules
Published:
These are rules to reread, not slogans to admire.
ai
Humanoid Robots Are Still a Bet
Published:
Current LLMs are already useful, but they still have several hard limits.
A Professional Git Worktree Workflow with a Bare Repository
Published:
If you regularly switch between branches, keep separate runtime environments, or want AI agents to work without disturbing your main checkout, a bare repository plus git worktree is one of the cleanest setups.
ai-agent
Give AI Agents Sudo with SUDO_ASKPASS
Published:
When an agent cannot type a sudo password into a TTY, a short zenity askpass helper unlocks a stable sudo -A workflow.
algorithms
GraphHopper paths are edges, not nodes
Published:
GraphHopper makes a deliberate design choice: paths are represented by edges, not nodes. This matters for correctness (turn restrictions/costs), fidelity (multiple parallel edges between the same nodes), and efficiency (edge properties drive routing).
analysis
Problems of China’s Math Education for Students
Published:
An analysis of the systemic problems in China’s math education system, examining what works and what doesn’t, and comparing approaches with other countries.
android
Fix Android Java version in Flutter plugins (Pub cache script)
Published:
Having builds fail with:
appimage
Create a desktop entry for Cursor AppImage (with icon extraction)
Published:
Quick notes to make a Cursor AppImage launchable from your desktop menus and include a proper icon.
apple-silicon
Run WireGuard on Apple Silicon macOS with wg-quick and launchd
Published:
Quick notes for running a WireGuard tunnel on an Apple Silicon Mac with wg-quick and launchd.
appointment
VFS 签证预约系统访问慢，可以先检查 DNS
Published:
在中国使用 VFS 签证预约系统时，如果 Cloudflare 验证加载很慢、页面经常卡死或登录被临时锁定，可以先尝试把 DNS 改成 1.1.1.1 和 8.8.8.8。
architecture
Good Software Rules
Published:
These are rules to reread, not slogans to admire.
askpass
Give AI Agents Sudo with SUDO_ASKPASS
Published:
When an agent cannot type a sudo password into a TTY, a short zenity askpass helper unlocks a stable sudo -A workflow.
automation
Give AI Agents Sudo with SUDO_ASKPASS
Published:
When an agent cannot type a sudo password into a TTY, a short zenity askpass helper unlocks a stable sudo -A workflow.
Codex CLI 0.119.0 on Windows: prefix_rule for git is not usable
Published:
Quick note from testing codex cli 0.119.0 on Windows: prefix_rule was not practical for allowing common git commands in a reusable way.
autonomous-driving
HAL Across Domains: How Different Systems Define Hardware Abstraction Layers
Published:
The term ‘HAL’ means different things in different domains—from kernel-level platform abstraction to application-level sensor control. Understanding these differences helps clarify domain-specific architecture choices.
baidu
Using BaiduPCS-Go cli
Published:
BaiduPCS-Go is a command-line Baidu Netdisk client.
baidupcs-go
Using BaiduPCS-Go cli
Published:
BaiduPCS-Go is a command-line Baidu Netdisk client.
bare-repo
A Professional Git Worktree Workflow with a Bare Repository
Published:
If you regularly switch between branches, keep separate runtime environments, or want AI agents to work without disturbing your main checkout, a bare repository plus git worktree is one of the cleanest setups.
bash
Run WireGuard on Apple Silicon macOS with wg-quick and launchd
Published:
Quick notes for running a WireGuard tunnel on an Apple Silicon Mac with wg-quick and launchd.
battery
Set Dell Battery Charge Limits on Linux with cctk
Published:
| On Dell Latitude 5501, smbios-battery-ctl can read charge limits but cannot set them. Use Dell Command | Configure (cctk) to write Custom:50-80 to the EC. |
bioinformatics
Building a Bioinformatics Docker Environment with Python, R, and Jupyter Lab
Published:
A comprehensive Docker setup for bioinformatics work, featuring non-root user configuration, Python virtual environments, R with Seurat, and Jupyter Lab with multi-profile docker-compose support.
ble
BLE Random Address Type Bits
Published:
BLE random device addresses encode their address type in the two most significant bits of the random address.
bluetooth
BLE Random Address Type Bits
Published:
BLE random device addresses encode their address type in the two most significant bits of the random address.
bootloader
GRUB’s GRUB_DEFAULT and GRUB_SAVEDEFAULT: Flexible but Confusing Design
Published:
GRUB splits reading and writing the saved boot entry across GRUB_DEFAULT and GRUB_SAVEDEFAULT. That flexibility helps admins and automation, but it exposes mechanism instead of user intent—and nested configfile menus can silently break remember-last-selection.
build
Fix Android Java version in Flutter plugins (Pub cache script)
Published:
Having builds fail with:
bundle-adjustment
OpenCV Calibration: Calling Hierarchies for H, F, E, and BA
Published:
Calling hierarchies for computing homography (H), fundamental matrix (F), essential matrix (E), and bundle adjustment (BA) in OpenCV.
calibration
OpenCV Calibration: Calling Hierarchies for H, F, E, and BA
Published:
Calling hierarchies for computing homography (H), fundamental matrix (F), essential matrix (E), and bundle adjustment (BA) in OpenCV.
cctk
Set Dell Battery Charge Limits on Linux with cctk
Published:
| On Dell Latitude 5501, smbios-battery-ctl can read charge limits but cannot set them. Use Dell Command | Configure (cctk) to write Custom:50-80 to the EC. |
china
Problems of China’s Math Education for Students
Published:
An analysis of the systemic problems in China’s math education system, examining what works and what doesn’t, and comparing approaches with other countries.
cia402
SV660N + MS1 from Scratch: EtherCAT, ROS 2, and a Smooth First Spin
Published:
Fresh Ubuntu 24.04 to a smooth SV660N/MS1 spin: wire the holding brake 24 V, build IgH with –disable-eoe, ROS 2 Jazzy + motor_drive, reach panel _88rn, run a soft CSP demo, and stop without EE081.
SV660N Keypad Panel Status Codes
Published:
SV660N 5-digit keypad: decode _28ry / AL blink, and panel-as-read faults (E6200, E6400, EE083) mapped to CoE 0x603F/0x203F.
clash-verge
Disable Clash Verge Rev Auto Check Update on Ubuntu
Published:
Turn off Clash Verge Rev update checks by setting auto_check_update: false in verge.yaml — a setting the GUI does not expose.
Fix Clash Verge TUN Mode on Ubuntu: operation not permitted
Published:
Clash Verge TUN mode is useful because it gives you system-wide proxying without configuring every application separately.
clash-verge-rev
Disable Clash Verge Rev Auto Check Update on Ubuntu
Published:
Turn off Clash Verge Rev update checks by setting auto_check_update: false in verge.yaml — a setting the GUI does not expose.
cleanup
Free Disk Space by Cleaning Stale Snap Revisions on Ubuntu
Published:
How I reclaimed about 2.8 GB from /var/lib/snapd/snaps on Ubuntu 24.04 by removing disabled Snap revisions and unused GNOME platform snaps.
cloudflare
VFS 签证预约系统访问慢，可以先检查 DNS
Published:
在中国使用 VFS 签证预约系统时，如果 Cloudflare 验证加载很慢、页面经常卡死或登录被临时锁定，可以先尝试把 DNS 改成 1.1.1.1 和 8.8.8.8。
codex
VS Code Codex Extension UI Freeze May Be Caused by Missing Shell Environment
Published:
Sometimes the Codex extension in VS Code can get stuck even though the Codex CLI still works normally.
Codex CLI 0.119.0 on Windows: prefix_rule for git is not usable
Published:
Quick note from testing codex cli 0.119.0 on Windows: prefix_rule was not practical for allowing common git commands in a reusable way.
colcon
Why ROS 2 Demands System Python (And How to Fix Virtual Environment Conflicts)
Published:
Standard Python virtual environments hide ROS 2 apt packages from colcon. Use –system-site-packages so pip stays isolated while builds can still import em, catkin_pkg, and friends.
command-line
Command-Line Scripts for Virtual Machine Management with Libvirt/KVM/QEMU
Published:
A collection of command-line scripts and tools for managing virtual machines using Libvirt, KVM, and QEMU, covering common VM operations, automation, and best practices.
computer-vision
OpenCV Calibration: Calling Hierarchies for H, F, E, and BA
Published:
Calling hierarchies for computing homography (H), fundamental matrix (F), essential matrix (E), and bundle adjustment (BA) in OpenCV.
Gold-Standard Error vs. Symmetric Transfer Error
Published:
Why gold-standard geometric error and symmetric transfer error differ, and when each is appropriate for evaluation and optimization.
Metric Rectification: Two Constraints from a Circle or Length Ratios
Published:
Why a circle becomes an ellipse after affine distortion, and how that ellipse (or two known length ratios) provides the two constraints needed for metric rectification.
Planar Homology: Applications and Intuition
Published:
Exploring the applications and intuitive understanding of planar homologies in projective geometry, computer vision, and geometric transformations.
Solving OpenGL/EGL Problems When Running ORB-SLAM3 in Docker Container on NVIDIA GPU Host
Published:
A guide to resolving OpenGL/EGL initialization and rendering issues when running ORB-SLAM3 in Docker containers on hosts with NVIDIA GPUs, covering proper GPU passthrough, EGL context setup, and common pitfalls.
config
Disable Clash Verge Rev Auto Check Update on Ubuntu
Published:
Turn off Clash Verge Rev update checks by setting auto_check_update: false in verge.yaml — a setting the GUI does not expose.
containerization
Solving OpenGL/EGL Problems When Running ORB-SLAM3 in Docker Container on NVIDIA GPU Host
Published:
A guide to resolving OpenGL/EGL initialization and rendering issues when running ORB-SLAM3 in Docker containers on hosts with NVIDIA GPUs, covering proper GPU passthrough, EGL context setup, and common pitfalls.
Building a Bioinformatics Docker Environment with Python, R, and Jupyter Lab
Published:
A comprehensive Docker setup for bioinformatics work, featuring non-root user configuration, Python virtual environments, R with Seurat, and Jupyter Lab with multi-profile docker-compose support.
context-menu
Add VS Code to the Nautilus Context Menu on Ubuntu
Published:
Use a Nautilus Python extension to put Open in VS Code on right-click for files, folders, and empty folder backgrounds.
control-systems
Learning Notes: Control Systems Engineering (Nise 7th, 2015)
Published:
Shared learning notes for Nise Control Systems Engineering 7th Edition — review questions with my answers and LLM answers side by side.
csp
SV660N + MS1 from Scratch: EtherCAT, ROS 2, and a Smooth First Spin
Published:
Fresh Ubuntu 24.04 to a smooth SV660N/MS1 spin: wire the holding brake 24 V, build IgH with –disable-eoe, ROS 2 Jazzy + motor_drive, reach panel _88rn, run a soft CSP demo, and stop without EE081.
cursor
Give AI Agents Sudo with SUDO_ASKPASS
Published:
When an agent cannot type a sudo password into a TTY, a short zenity askpass helper unlocks a stable sudo -A workflow.
Create a desktop entry for Cursor AppImage (with icon extraction)
Published:
Quick notes to make a Cursor AppImage launchable from your desktop menus and include a proper icon.
debugging
VS Code Codex Extension UI Freeze May Be Caused by Missing Shell Environment
Published:
Sometimes the Codex extension in VS Code can get stuck even though the Codex CLI still works normally.
dell
Set Dell Battery Charge Limits on Linux with cctk
Published:
| On Dell Latitude 5501, smbios-battery-ctl can read charge limits but cannot set them. Use Dell Command | Configure (cctk) to write Custom:50-80 to the EC. |
Dell Latitude 5501 Linux Deep Sleep Experiment
Published:
I tried to reduce suspend battery drain on my Dell Latitude 5501 running Ubuntu 24.04.
design
GRUB’s GRUB_DEFAULT and GRUB_SAVEDEFAULT: Flexible but Confusing Design
Published:
GRUB splits reading and writing the saved boot entry across GRUB_DEFAULT and GRUB_SAVEDEFAULT. That flexibility helps admins and automation, but it exposes mechanism instead of user intent—and nested configfile menus can silently break remember-last-selection.
desktop
Create a desktop entry for Cursor AppImage (with icon extraction)
Published:
Quick notes to make a Cursor AppImage launchable from your desktop menus and include a proper icon.
disk-space
Free Disk Space by Cleaning Stale Snap Revisions on Ubuntu
Published:
How I reclaimed about 2.8 GB from /var/lib/snapd/snaps on Ubuntu 24.04 by removing disabled Snap revisions and unused GNOME platform snaps.
dkms
How to Install Ubuntu 24.04 Real-Time Kernel (PREEMPT_RT) on a Dual-GPU Laptop
Published:
Install ubuntu-realtime on Ubuntu 24.04 with Intel + NVIDIA hybrid graphics: why apt stalls at 2%, why NVIDIA DKMS fails against PREEMPT_RT, how to finish dpkg, and how to restore nvidia-smi on the generic kernel only.
dns
VFS 签证预约系统访问慢，可以先检查 DNS
Published:
在中国使用 VFS 签证预约系统时，如果 Cloudflare 验证加载很慢、页面经常卡死或登录被临时锁定，可以先尝试把 DNS 改成 1.1.1.1 和 8.8.8.8。
docker
GitLab in Docker showed 502 after restart: root cause and fix
Published:
I ran into a GitLab outage in a Docker-based deployment where the web UI returned 502 Bad Gateway, even though the container itself was still running and even showed as healthy in docker ps.
Solving OpenGL/EGL Problems When Running ORB-SLAM3 in Docker Container on NVIDIA GPU Host
Published:
A guide to resolving OpenGL/EGL initialization and rendering issues when running ORB-SLAM3 in Docker containers on hosts with NVIDIA GPUs, covering proper GPU passthrough, EGL context setup, and common pitfalls.
Building a Bioinformatics Docker Environment with Python, R, and Jupyter Lab
Published:
A comprehensive Docker setup for bioinformatics work, featuring non-root user configuration, Python virtual environments, R with Seurat, and Jupyter Lab with multi-profile docker-compose support.
download
Using BaiduPCS-Go cli
Published:
BaiduPCS-Go is a command-line Baidu Netdisk client.
edge-based
GraphHopper paths are edges, not nodes
Published:
GraphHopper makes a deliberate design choice: paths are represented by edges, not nodes. This matters for correctness (turn restrictions/costs), fidelity (multiple parallel edges between the same nodes), and efficiency (edge properties drive routing).
education
Problems of China’s Math Education for Students
Published:
An analysis of the systemic problems in China’s math education system, examining what works and what doesn’t, and comparing approaches with other countries.
egl
Solving OpenGL/EGL Problems When Running ORB-SLAM3 in Docker Container on NVIDIA GPU Host
Published:
A guide to resolving OpenGL/EGL initialization and rendering issues when running ORB-SLAM3 in Docker containers on hosts with NVIDIA GPUs, covering proper GPU passthrough, EGL context setup, and common pitfalls.
embedded-systems
HAL Across Domains: How Different Systems Define Hardware Abstraction Layers
Published:
The term ‘HAL’ means different things in different domains—from kernel-level platform abstraction to application-level sensor control. Understanding these differences helps clarify domain-specific architecture choices.
engineering
Humanoid Robots Are Still a Bet
Published:
Current LLMs are already useful, but they still have several hard limits.
Good Software Rules
Published:
These are rules to reread, not slogans to admire.
environment
VS Code Codex Extension UI Freeze May Be Caused by Missing Shell Environment
Published:
Sometimes the Codex extension in VS Code can get stuck even though the Codex CLI still works normally.
essential-matrix
OpenCV Calibration: Calling Hierarchies for H, F, E, and BA
Published:
Calling hierarchies for computing homography (H), fundamental matrix (F), essential matrix (E), and bundle adjustment (BA) in OpenCV.
estimation
Gold-Standard Error vs. Symmetric Transfer Error
Published:
Why gold-standard geometric error and symmetric transfer error differ, and when each is appropriate for evaluation and optimization.
ethercat
SV660N + MS1 from Scratch: EtherCAT, ROS 2, and a Smooth First Spin
Published:
Fresh Ubuntu 24.04 to a smooth SV660N/MS1 spin: wire the holding brake 24 V, build IgH with –disable-eoe, ROS 2 Jazzy + motor_drive, reach panel _88rn, run a soft CSP demo, and stop without EE081.
SV660N Keypad Panel Status Codes
Published:
SV660N 5-digit keypad: decode _28ry / AL blink, and panel-as-read faults (E6200, E6400, EE083) mapped to CoE 0x603F/0x203F.
How to Install Ubuntu 24.04 Real-Time Kernel (PREEMPT_RT) on a Dual-GPU Laptop
Published:
Install ubuntu-realtime on Ubuntu 24.04 with Intel + NVIDIA hybrid graphics: why apt stalls at 2%, why NVIDIA DKMS fails against PREEMPT_RT, how to finish dpkg, and how to restore nvidia-smi on the generic kernel only.
extension
VS Code Codex Extension UI Freeze May Be Caused by Missing Shell Environment
Published:
Sometimes the Codex extension in VS Code can get stuck even though the Codex CLI still works normally.
feedback
Learning Notes: Control Systems Engineering (Nise 7th, 2015)
Published:
Shared learning notes for Nise Control Systems Engineering 7th Edition — review questions with my answers and LLM answers side by side.
firmware-updater
Free Disk Space by Cleaning Stale Snap Revisions on Ubuntu
Published:
How I reclaimed about 2.8 GB from /var/lib/snapd/snaps on Ubuntu 24.04 by removing disabled Snap revisions and unused GNOME platform snaps.
flutter
Fix Android Java version in Flutter plugins (Pub cache script)
Published:
Having builds fail with:
fundamental-matrix
OpenCV Calibration: Calling Hierarchies for H, F, E, and BA
Published:
Calling hierarchies for computing homography (H), fundamental matrix (F), essential matrix (E), and bundle adjustment (BA) in OpenCV.
geometric-error
Gold-Standard Error vs. Symmetric Transfer Error
Published:
Why gold-standard geometric error and symmetric transfer error differ, and when each is appropriate for evaluation and optimization.
geometry
Planar Homology: Applications and Intuition
Published:
Exploring the applications and intuitive understanding of planar homologies in projective geometry, computer vision, and geometric transformations.
git
Syncing Two Git Machines Over LAN Without a Central Server
Published:
Sometimes the normal Git server is temporarily unavailable, but you still need to move work between two machines on the same local network.
A Professional Git Worktree Workflow with a Bare Repository
Published:
If you regularly switch between branches, keep separate runtime environments, or want AI agents to work without disturbing your main checkout, a bare repository plus git worktree is one of the cleanest setups.
Codex CLI 0.119.0 on Windows: prefix_rule for git is not usable
Published:
Quick note from testing codex cli 0.119.0 on Windows: prefix_rule was not practical for allowing common git commands in a reusable way.
gitlab
GitLab in Docker showed 502 after restart: root cause and fix
Published:
I ran into a GitLab outage in a Docker-based deployment where the web UI returned 502 Bad Gateway, even though the container itself was still running and even showed as healthy in docker ps.
gnome
Add VS Code to the Nautilus Context Menu on Ubuntu
Published:
Use a Nautilus Python extension to put Open in VS Code on right-click for files, folders, and empty folder backgrounds.
Ubuntu 下给微信添加显示/隐藏快捷键
Published:
Linux 版微信在 Ubuntu 中没有内置的显示/隐藏窗口快捷键，可以用 xdotool 和 GNOME 自定义快捷键实现一个类似的切换功能。
gpu
Solving OpenGL/EGL Problems When Running ORB-SLAM3 in Docker Container on NVIDIA GPU Host
Published:
A guide to resolving OpenGL/EGL initialization and rendering issues when running ORB-SLAM3 in Docker containers on hosts with NVIDIA GPUs, covering proper GPU passthrough, EGL context setup, and common pitfalls.
gradle
Fix Android Java version in Flutter plugins (Pub cache script)
Published:
Having builds fail with:
graphhopper
GraphHopper paths are edges, not nodes
Published:
GraphHopper makes a deliberate design choice: paths are represented by edges, not nodes. This matters for correctness (turn restrictions/costs), fidelity (multiple parallel edges between the same nodes), and efficiency (edge properties drive routing).
graphs
GraphHopper paths are edges, not nodes
Published:
GraphHopper makes a deliberate design choice: paths are represented by edges, not nodes. This matters for correctness (turn restrictions/costs), fidelity (multiple parallel edges between the same nodes), and efficiency (edge properties drive routing).
grub
GRUB’s GRUB_DEFAULT and GRUB_SAVEDEFAULT: Flexible but Confusing Design
Published:
GRUB splits reading and writing the saved boot entry across GRUB_DEFAULT and GRUB_SAVEDEFAULT. That flexibility helps admins and automation, but it exposes mechanism instead of user intent—and nested configfile menus can silently break remember-last-selection.
hal
HAL Across Domains: How Different Systems Define Hardware Abstraction Layers
Published:
The term ‘HAL’ means different things in different domains—from kernel-level platform abstraction to application-level sensor control. Understanding these differences helps clarify domain-specific architecture choices.
hardware-abstraction
HAL Across Domains: How Different Systems Define Hardware Abstraction Layers
Published:
The term ‘HAL’ means different things in different domains—from kernel-level platform abstraction to application-level sensor control. Understanding these differences helps clarify domain-specific architecture choices.
homography
OpenCV Calibration: Calling Hierarchies for H, F, E, and BA
Published:
Calling hierarchies for computing homography (H), fundamental matrix (F), essential matrix (E), and bundle adjustment (BA) in OpenCV.
Gold-Standard Error vs. Symmetric Transfer Error
Published:
Why gold-standard geometric error and symmetric transfer error differ, and when each is appropriate for evaluation and optimization.
Metric Rectification: Two Constraints from a Circle or Length Ratios
Published:
Why a circle becomes an ellipse after affine distortion, and how that ellipse (or two known length ratios) provides the two constraints needed for metric rectification.
homology
Planar Homology: Applications and Intuition
Published:
Exploring the applications and intuitive understanding of planar homologies in projective geometry, computer vision, and geometric transformations.
humanoid
Humanoid Robots Are Still a Bet
Published:
Current LLMs are already useful, but they still have several hard limits.
hybrid-graphics
How to Install Ubuntu 24.04 Real-Time Kernel (PREEMPT_RT) on a Dual-GPU Laptop
Published:
Install ubuntu-realtime on Ubuntu 24.04 with Intel + NVIDIA hybrid graphics: why apt stalls at 2%, why NVIDIA DKMS fails against PREEMPT_RT, how to finish dpkg, and how to restore nvidia-smi on the generic kernel only.
Fixing llvmpipe on Ubuntu Wayland with Intel + NVIDIA Hybrid Graphics
Published:
How I diagnosed a misleading llvmpipe report on Ubuntu Wayland and fixed the real Xwayland/GLX fallback by updating Xwayland and Xorg core packages.
Fixing XWayland High CPU Spikes on Ubuntu 24.04 with Intel + NVIDIA Hybrid Graphics
Published:
How installing the proprietary NVIDIA driver fixed repeated XWayland CPU spikes when launching Electron and Chromium apps on an Ubuntu 24.04 Intel + NVIDIA hybrid laptop.
igh
SV660N + MS1 from Scratch: EtherCAT, ROS 2, and a Smooth First Spin
Published:
Fresh Ubuntu 24.04 to a smooth SV660N/MS1 spin: wire the holding brake 24 V, build IgH with –disable-eoe, ROS 2 Jazzy + motor_drive, reach panel _88rn, run a soft CSP demo, and stop without EE081.
SV660N Keypad Panel Status Codes
Published:
SV660N 5-digit keypad: decode _28ry / AL blink, and panel-as-read faults (E6200, E6400, EE083) mapped to CoE 0x603F/0x203F.
inovance
SV660N + MS1 from Scratch: EtherCAT, ROS 2, and a Smooth First Spin
Published:
Fresh Ubuntu 24.04 to a smooth SV660N/MS1 spin: wire the holding brake 24 V, build IgH with –disable-eoe, ROS 2 Jazzy + motor_drive, reach panel _88rn, run a soft CSP demo, and stop without EE081.
SV660N Keypad Panel Status Codes
Published:
SV660N 5-digit keypad: decode _28ry / AL blink, and panel-as-read faults (E6200, E6400, EE083) mapped to CoE 0x603F/0x203F.
input-method
macOS 下清理应用状态修复 WeType 简繁切换残留问题
Published:
macOS 下遇到一个 WeType 的奇怪问题：切换到繁体输入后，再切回简体输入，有些字仍然会按繁体输出，例如 還、總、覆 这类结果会残留在简体模式里。
intel
Fixing llvmpipe on Ubuntu Wayland with Intel + NVIDIA Hybrid Graphics
Published:
How I diagnosed a misleading llvmpipe report on Ubuntu Wayland and fixed the real Xwayland/GLX fallback by updating Xwayland and Xorg core packages.
java
Fix Android Java version in Flutter plugins (Pub cache script)
Published:
Having builds fail with:
GraphHopper paths are edges, not nodes
Published:
GraphHopper makes a deliberate design choice: paths are represented by edges, not nodes. This matters for correctness (turn restrictions/costs), fidelity (multiple parallel edges between the same nodes), and efficiency (edge properties drive routing).
jazzy
SV660N + MS1 from Scratch: EtherCAT, ROS 2, and a Smooth First Spin
Published:
Fresh Ubuntu 24.04 to a smooth SV660N/MS1 spin: wire the holding brake 24 V, build IgH with –disable-eoe, ROS 2 Jazzy + motor_drive, reach panel _88rn, run a soft CSP demo, and stop without EE081.
jupyter
Setting Up Jupyter Terminal Keyboard Shortcut
Published:
Learn how to quickly create a new terminal in Jupyter using a custom keyboard shortcut. This is especially useful for developers who frequently need to run shell commands while working in Jupyter notebooks.
Building a Bioinformatics Docker Environment with Python, R, and Jupyter Lab
Published:
A comprehensive Docker setup for bioinformatics work, featuring non-root user configuration, Python virtual environments, R with Seurat, and Jupyter Lab with multi-profile docker-compose support.
keyboard-shortcut
Setting Up Jupyter Terminal Keyboard Shortcut
Published:
Learn how to quickly create a new terminal in Jupyter using a custom keyboard shortcut. This is especially useful for developers who frequently need to run shell commands while working in Jupyter notebooks.
kotlin
Fix Android Java version in Flutter plugins (Pub cache script)
Published:
Having builds fail with:
kvm
Command-Line Scripts for Virtual Machine Management with Libvirt/KVM/QEMU
Published:
A collection of command-line scripts and tools for managing virtual machines using Libvirt, KVM, and QEMU, covering common VM operations, automation, and best practices.
lan
Syncing Two Git Machines Over LAN Without a Central Server
Published:
Sometimes the normal Git server is temporarily unavailable, but you still need to move work between two machines on the same local network.
latitude-5501
Set Dell Battery Charge Limits on Linux with cctk
Published:
| On Dell Latitude 5501, smbios-battery-ctl can read charge limits but cannot set them. Use Dell Command | Configure (cctk) to write Custom:50-80 to the EC. |
launchd
Run WireGuard on Apple Silicon macOS with wg-quick and launchd
Published:
Quick notes for running a WireGuard tunnel on an Apple Silicon Mac with wg-quick and launchd.
libvirt
Command-Line Scripts for Virtual Machine Management with Libvirt/KVM/QEMU
Published:
A collection of command-line scripts and tools for managing virtual machines using Libvirt, KVM, and QEMU, covering common VM operations, automation, and best practices.
linux
Set Dell Battery Charge Limits on Linux with cctk
Published:
| On Dell Latitude 5501, smbios-battery-ctl can read charge limits but cannot set them. Use Dell Command | Configure (cctk) to write Custom:50-80 to the EC. |
Disable Clash Verge Rev Auto Check Update on Ubuntu
Published:
Turn off Clash Verge Rev update checks by setting auto_check_update: false in verge.yaml — a setting the GUI does not expose.
GRUB’s GRUB_DEFAULT and GRUB_SAVEDEFAULT: Flexible but Confusing Design
Published:
GRUB splits reading and writing the saved boot entry across GRUB_DEFAULT and GRUB_SAVEDEFAULT. That flexibility helps admins and automation, but it exposes mechanism instead of user intent—and nested configfile menus can silently break remember-last-selection.
How to Install Ubuntu 24.04 Real-Time Kernel (PREEMPT_RT) on a Dual-GPU Laptop
Published:
Install ubuntu-realtime on Ubuntu 24.04 with Intel + NVIDIA hybrid graphics: why apt stalls at 2%, why NVIDIA DKMS fails against PREEMPT_RT, how to finish dpkg, and how to restore nvidia-smi on the generic kernel only.
Add VS Code to the Nautilus Context Menu on Ubuntu
Published:
Use a Nautilus Python extension to put Open in VS Code on right-click for files, folders, and empty folder backgrounds.
Give AI Agents Sudo with SUDO_ASKPASS
Published:
When an agent cannot type a sudo password into a TTY, a short zenity askpass helper unlocks a stable sudo -A workflow.
Free Disk Space by Cleaning Stale Snap Revisions on Ubuntu
Published:
How I reclaimed about 2.8 GB from /var/lib/snapd/snaps on Ubuntu 24.04 by removing disabled Snap revisions and unused GNOME platform snaps.
Fixing llvmpipe on Ubuntu Wayland with Intel + NVIDIA Hybrid Graphics
Published:
How I diagnosed a misleading llvmpipe report on Ubuntu Wayland and fixed the real Xwayland/GLX fallback by updating Xwayland and Xorg core packages.
Fix Clash Verge TUN Mode on Ubuntu: operation not permitted
Published:
Clash Verge TUN mode is useful because it gives you system-wide proxying without configuring every application separately.
Dell Latitude 5501 Linux Deep Sleep Experiment
Published:
I tried to reduce suspend battery drain on my Dell Latitude 5501 running Ubuntu 24.04.
Ubuntu 下给微信添加显示/隐藏快捷键
Published:
Linux 版微信在 Ubuntu 中没有内置的显示/隐藏窗口快捷键，可以用 xdotool 和 GNOME 自定义快捷键实现一个类似的切换功能。
Fixing XWayland High CPU Spikes on Ubuntu 24.04 with Intel + NVIDIA Hybrid Graphics
Published:
How installing the proprietary NVIDIA driver fixed repeated XWayland CPU spikes when launching Electron and Chromium apps on an Ubuntu 24.04 Intel + NVIDIA hybrid laptop.
Why SSH Still Asks for a Password After PasswordAuthentication no
Published:
If you set PasswordAuthentication no in sshd_config and SSH still accepts a password, the problem is usually not your keys. The problem is that OpenSSH can still allow password-like login through KbdInteractiveAuthentication, often backed by PAM.
Command-Line Scripts for Virtual Machine Management with Libvirt/KVM/QEMU
Published:
A collection of command-line scripts and tools for managing virtual machines using Libvirt, KVM, and QEMU, covering common VM operations, automation, and best practices.
Create a desktop entry for Cursor AppImage (with icon extraction)
Published:
Quick notes to make a Cursor AppImage launchable from your desktop menus and include a proper icon.
linuxcnc
Why LinuxCNC Drivers Are HAL Components: Understanding a Domain-Specific Architecture
Published:
The HAL is not necessarily a module — it’s a boundary of responsibility between hardware-dependent and hardware-independent code.
llvmpipe
Fixing llvmpipe on Ubuntu Wayland with Intel + NVIDIA Hybrid Graphics
Published:
How I diagnosed a misleading llvmpipe report on Ubuntu Wayland and fixed the real Xwayland/GLX fallback by updating Xwayland and Xorg core packages.
macos
macOS 下清理应用状态修复 WeType 简繁切换残留问题
Published:
macOS 下遇到一个 WeType 的奇怪问题：切换到繁体输入后，再切回简体输入，有些字仍然会按繁体输出，例如 還、總、覆 这类结果会残留在简体模式里。
Run WireGuard on Apple Silicon macOS with wg-quick and launchd
Published:
Quick notes for running a WireGuard tunnel on an Apple Silicon Mac with wg-quick and launchd.
Why SSH Still Asks for a Password After PasswordAuthentication no
Published:
If you set PasswordAuthentication no in sshd_config and SSH still accepts a password, the problem is usually not your keys. The problem is that OpenSSH can still allow password-like login through KbdInteractiveAuthentication, often backed by PAM.
math
Problems of China’s Math Education for Students
Published:
An analysis of the systemic problems in China’s math education system, examining what works and what doesn’t, and comparing approaches with other countries.
mathematics
Planar Homology: Applications and Intuition
Published:
Exploring the applications and intuitive understanding of planar homologies in projective geometry, computer vision, and geometric transformations.
matlab
Learning Notes: Control Systems Engineering (Nise 7th, 2015)
Published:
Shared learning notes for Nise Control Systems Engineering 7th Edition — review questions with my answers and LLM answers side by side.
mesa
Free Disk Space by Cleaning Stale Snap Revisions on Ubuntu
Published:
How I reclaimed about 2.8 GB from /var/lib/snapd/snaps on Ubuntu 24.04 by removing disabled Snap revisions and unused GNOME platform snaps.
mihomo
Fix Clash Verge TUN Mode on Ubuntu: operation not permitted
Published:
Clash Verge TUN mode is useful because it gives you system-wide proxying without configuring every application separately.
ms1
SV660N + MS1 from Scratch: EtherCAT, ROS 2, and a Smooth First Spin
Published:
Fresh Ubuntu 24.04 to a smooth SV660N/MS1 spin: wire the holding brake 24 V, build IgH with –disable-eoe, ROS 2 Jazzy + motor_drive, reach panel _88rn, run a soft CSP demo, and stop without EE081.
nautilus
Add VS Code to the Nautilus Context Menu on Ubuntu
Published:
Use a Nautilus Python extension to put Open in VS Code on right-click for files, folders, and empty folder backgrounds.
navigation
GraphHopper paths are edges, not nodes
Published:
GraphHopper makes a deliberate design choice: paths are represented by edges, not nodes. This matters for correctness (turn restrictions/costs), fidelity (multiple parallel edges between the same nodes), and efficiency (edge properties drive routing).
netdisk
Using BaiduPCS-Go cli
Published:
BaiduPCS-Go is a command-line Baidu Netdisk client.
newbie
SV660N + MS1 from Scratch: EtherCAT, ROS 2, and a Smooth First Spin
Published:
Fresh Ubuntu 24.04 to a smooth SV660N/MS1 spin: wire the holding brake 24 V, build IgH with –disable-eoe, ROS 2 Jazzy + motor_drive, reach panel _88rn, run a soft CSP demo, and stop without EE081.
nginx
GitLab in Docker showed 502 after restart: root cause and fix
Published:
I ran into a GitLab outage in a Docker-based deployment where the web UI returned 502 Bad Gateway, even though the container itself was still running and even showed as healthy in docker ps.
nise
Learning Notes: Control Systems Engineering (Nise 7th, 2015)
Published:
Shared learning notes for Nise Control Systems Engineering 7th Edition — review questions with my answers and LLM answers side by side.
notes
Learning Notes: Control Systems Engineering (Nise 7th, 2015)
Published:
Shared learning notes for Nise Control Systems Engineering 7th Edition — review questions with my answers and LLM answers side by side.
nouveau
Fixing XWayland High CPU Spikes on Ubuntu 24.04 with Intel + NVIDIA Hybrid Graphics
Published:
How installing the proprietary NVIDIA driver fixed repeated XWayland CPU spikes when launching Electron and Chromium apps on an Ubuntu 24.04 Intel + NVIDIA hybrid laptop.
nvidia
How to Install Ubuntu 24.04 Real-Time Kernel (PREEMPT_RT) on a Dual-GPU Laptop
Published:
Install ubuntu-realtime on Ubuntu 24.04 with Intel + NVIDIA hybrid graphics: why apt stalls at 2%, why NVIDIA DKMS fails against PREEMPT_RT, how to finish dpkg, and how to restore nvidia-smi on the generic kernel only.
Fixing llvmpipe on Ubuntu Wayland with Intel + NVIDIA Hybrid Graphics
Published:
How I diagnosed a misleading llvmpipe report on Ubuntu Wayland and fixed the real Xwayland/GLX fallback by updating Xwayland and Xorg core packages.
Dell Latitude 5501 Linux Deep Sleep Experiment
Published:
I tried to reduce suspend battery drain on my Dell Latitude 5501 running Ubuntu 24.04.
Fixing XWayland High CPU Spikes on Ubuntu 24.04 with Intel + NVIDIA Hybrid Graphics
Published:
How installing the proprietary NVIDIA driver fixed repeated XWayland CPU spikes when launching Electron and Chromium apps on an Ubuntu 24.04 Intel + NVIDIA hybrid laptop.
Solving OpenGL/EGL Problems When Running ORB-SLAM3 in Docker Container on NVIDIA GPU Host
Published:
A guide to resolving OpenGL/EGL initialization and rendering issues when running ORB-SLAM3 in Docker containers on hosts with NVIDIA GPUs, covering proper GPU passthrough, EGL context setup, and common pitfalls.
opencv
OpenCV Calibration: Calling Hierarchies for H, F, E, and BA
Published:
Calling hierarchies for computing homography (H), fundamental matrix (F), essential matrix (E), and bundle adjustment (BA) in OpenCV.
opengl
Solving OpenGL/EGL Problems When Running ORB-SLAM3 in Docker Container on NVIDIA GPU Host
Published:
A guide to resolving OpenGL/EGL initialization and rendering issues when running ORB-SLAM3 in Docker containers on hosts with NVIDIA GPUs, covering proper GPU passthrough, EGL context setup, and common pitfalls.
openssh
Why SSH Still Asks for a Password After PasswordAuthentication no
Published:
If you set PasswordAuthentication no in sshd_config and SSH still accepts a password, the problem is usually not your keys. The problem is that OpenSSH can still allow password-like login through KbdInteractiveAuthentication, often backed by PAM.
Install OpenSSH Server on Windows from the Win32-OpenSSH release zip
Published:
Quick notes for setting up the Windows OpenSSH server from the OpenSSH-Win64.zip package.
openssl
VS Code Codex Extension UI Freeze May Be Caused by Missing Shell Environment
Published:
Sometimes the Codex extension in VS Code can get stuck even though the Codex CLI still works normally.
orbslam3
Solving OpenGL/EGL Problems When Running ORB-SLAM3 in Docker Container on NVIDIA GPU Host
Published:
A guide to resolving OpenGL/EGL initialization and rendering issues when running ORB-SLAM3 in Docker containers on hosts with NVIDIA GPUs, covering proper GPU passthrough, EGL context setup, and common pitfalls.
pedagogy
Problems of China’s Math Education for Students
Published:
An analysis of the systemic problems in China’s math education system, examining what works and what doesn’t, and comparing approaches with other countries.
postgresql
GitLab in Docker showed 502 after restart: root cause and fix
Published:
I ran into a GitLab outage in a Docker-based deployment where the web UI returned 502 Bad Gateway, even though the container itself was still running and even showed as healthy in docker ps.
powershell
Codex CLI 0.119.0 on Windows: prefix_rule for git is not usable
Published:
Quick note from testing codex cli 0.119.0 on Windows: prefix_rule was not practical for allowing common git commands in a reusable way.
Install OpenSSH Server on Windows from the Win32-OpenSSH release zip
Published:
Quick notes for setting up the Windows OpenSSH server from the OpenSSH-Win64.zip package.
preempt-rt
SV660N + MS1 from Scratch: EtherCAT, ROS 2, and a Smooth First Spin
Published:
Fresh Ubuntu 24.04 to a smooth SV660N/MS1 spin: wire the holding brake 24 V, build IgH with –disable-eoe, ROS 2 Jazzy + motor_drive, reach panel _88rn, run a soft CSP demo, and stop without EE081.
How to Install Ubuntu 24.04 Real-Time Kernel (PREEMPT_RT) on a Dual-GPU Laptop
Published:
Install ubuntu-realtime on Ubuntu 24.04 with Intel + NVIDIA hybrid graphics: why apt stalls at 2%, why NVIDIA DKMS fails against PREEMPT_RT, how to finish dpkg, and how to restore nvidia-smi on the generic kernel only.
productivity
Setting Up Jupyter Terminal Keyboard Shortcut
Published:
Learn how to quickly create a new terminal in Jupyter using a custom keyboard shortcut. This is especially useful for developers who frequently need to run shell commands while working in Jupyter notebooks.
projective-geometry
Metric Rectification: Two Constraints from a Circle or Length Ratios
Published:
Why a circle becomes an ellipse after affine distortion, and how that ellipse (or two known length ratios) provides the two constraints needed for metric rectification.
Planar Homology: Applications and Intuition
Published:
Exploring the applications and intuitive understanding of planar homologies in projective geometry, computer vision, and geometric transformations.
pub-cache
Fix Android Java version in Flutter plugins (Pub cache script)
Published:
Having builds fail with:
python
Why ROS 2 Demands System Python (And How to Fix Virtual Environment Conflicts)
Published:
Standard Python virtual environments hide ROS 2 apt packages from colcon. Use –system-site-packages so pip stays isolated while builds can still import em, catkin_pkg, and friends.
Add VS Code to the Nautilus Context Menu on Ubuntu
Published:
Use a Nautilus Python extension to put Open in VS Code on right-click for files, folders, and empty folder backgrounds.
Building a Bioinformatics Docker Environment with Python, R, and Jupyter Lab
Published:
A comprehensive Docker setup for bioinformatics work, featuring non-root user configuration, Python virtual environments, R with Seurat, and Jupyter Lab with multi-profile docker-compose support.
qemu
Command-Line Scripts for Virtual Machine Management with Libvirt/KVM/QEMU
Published:
A collection of command-line scripts and tools for managing virtual machines using Libvirt, KVM, and QEMU, covering common VM operations, automation, and best practices.
r
Building a Bioinformatics Docker Environment with Python, R, and Jupyter Lab
Published:
A comprehensive Docker setup for bioinformatics work, featuring non-root user configuration, Python virtual environments, R with Seurat, and Jupyter Lab with multi-profile docker-compose support.
realtime
How to Install Ubuntu 24.04 Real-Time Kernel (PREEMPT_RT) on a Dual-GPU Laptop
Published:
Install ubuntu-realtime on Ubuntu 24.04 with Intel + NVIDIA hybrid graphics: why apt stalls at 2%, why NVIDIA DKMS fails against PREEMPT_RT, how to finish dpkg, and how to restore nvidia-smi on the generic kernel only.
rectification
Metric Rectification: Two Constraints from a Circle or Length Ratios
Published:
Why a circle becomes an ellipse after affine distortion, and how that ellipse (or two known length ratios) provides the two constraints needed for metric rectification.
robotics
How to Install Ubuntu 24.04 Real-Time Kernel (PREEMPT_RT) on a Dual-GPU Laptop
Published:
Install ubuntu-realtime on Ubuntu 24.04 with Intel + NVIDIA hybrid graphics: why apt stalls at 2%, why NVIDIA DKMS fails against PREEMPT_RT, how to finish dpkg, and how to restore nvidia-smi on the generic kernel only.
Humanoid Robots Are Still a Bet
Published:
Current LLMs are already useful, but they still have several hard limits.
HAL Across Domains: How Different Systems Define Hardware Abstraction Layers
Published:
The term ‘HAL’ means different things in different domains—from kernel-level platform abstraction to application-level sensor control. Understanding these differences helps clarify domain-specific architecture choices.
ros2
SV660N + MS1 from Scratch: EtherCAT, ROS 2, and a Smooth First Spin
Published:
Fresh Ubuntu 24.04 to a smooth SV660N/MS1 spin: wire the holding brake 24 V, build IgH with –disable-eoe, ROS 2 Jazzy + motor_drive, reach panel _88rn, run a soft CSP demo, and stop without EE081.
Why ROS 2 Demands System Python (And How to Fix Virtual Environment Conflicts)
Published:
Standard Python virtual environments hide ROS 2 apt packages from colcon. Use –system-site-packages so pip stays isolated while builds can still import em, catkin_pkg, and friends.
routing
GraphHopper paths are edges, not nodes
Published:
GraphHopper makes a deliberate design choice: paths are represented by edges, not nodes. This matters for correctness (turn restrictions/costs), fidelity (multiple parallel edges between the same nodes), and efficiency (edge properties drive routing).
scripts
Command-Line Scripts for Virtual Machine Management with Libvirt/KVM/QEMU
Published:
A collection of command-line scripts and tools for managing virtual machines using Libvirt, KVM, and QEMU, covering common VM operations, automation, and best practices.
security
Why SSH Still Asks for a Password After PasswordAuthentication no
Published:
If you set PasswordAuthentication no in sshd_config and SSH still accepts a password, the problem is usually not your keys. The problem is that OpenSSH can still allow password-like login through KbdInteractiveAuthentication, often backed by PAM.
servo
SV660N + MS1 from Scratch: EtherCAT, ROS 2, and a Smooth First Spin
Published:
Fresh Ubuntu 24.04 to a smooth SV660N/MS1 spin: wire the holding brake 24 V, build IgH with –disable-eoe, ROS 2 Jazzy + motor_drive, reach panel _88rn, run a soft CSP demo, and stop without EE081.
SV660N Keypad Panel Status Codes
Published:
SV660N 5-digit keypad: decode _28ry / AL blink, and panel-as-read faults (E6200, E6400, EE083) mapped to CoE 0x603F/0x203F.
seurat
Building a Bioinformatics Docker Environment with Python, R, and Jupyter Lab
Published:
A comprehensive Docker setup for bioinformatics work, featuring non-root user configuration, Python virtual environments, R with Seurat, and Jupyter Lab with multi-profile docker-compose support.
shortcut
Ubuntu 下给微信添加显示/隐藏快捷键
Published:
Linux 版微信在 Ubuntu 中没有内置的显示/隐藏窗口快捷键，可以用 xdotool 和 GNOME 自定义快捷键实现一个类似的切换功能。
sleep
Dell Latitude 5501 Linux Deep Sleep Experiment
Published:
I tried to reduce suspend battery drain on my Dell Latitude 5501 running Ubuntu 24.04.
smbios
Set Dell Battery Charge Limits on Linux with cctk
Published:
| On Dell Latitude 5501, smbios-battery-ctl can read charge limits but cannot set them. Use Dell Command | Configure (cctk) to write Custom:50-80 to the EC. |
snap
Free Disk Space by Cleaning Stale Snap Revisions on Ubuntu
Published:
How I reclaimed about 2.8 GB from /var/lib/snapd/snaps on Ubuntu 24.04 by removing disabled Snap revisions and unused GNOME platform snaps.
snapd
Free Disk Space by Cleaning Stale Snap Revisions on Ubuntu
Published:
How I reclaimed about 2.8 GB from /var/lib/snapd/snaps on Ubuntu 24.04 by removing disabled Snap revisions and unused GNOME platform snaps.
software
Good Software Rules
Published:
These are rules to reread, not slogans to admire.
ssh
Syncing Two Git Machines Over LAN Without a Central Server
Published:
Sometimes the normal Git server is temporarily unavailable, but you still need to move work between two machines on the same local network.
Why SSH Still Asks for a Password After PasswordAuthentication no
Published:
If you set PasswordAuthentication no in sshd_config and SSH still accepts a password, the problem is usually not your keys. The problem is that OpenSSH can still allow password-like login through KbdInteractiveAuthentication, often backed by PAM.
Install OpenSSH Server on Windows from the Win32-OpenSSH release zip
Published:
Quick notes for setting up the Windows OpenSSH server from the OpenSSH-Win64.zip package.
stacker
SV660N + MS1 from Scratch: EtherCAT, ROS 2, and a Smooth First Spin
Published:
Fresh Ubuntu 24.04 to a smooth SV660N/MS1 spin: wire the holding brake 24 V, build IgH with –disable-eoe, ROS 2 Jazzy + motor_drive, reach panel _88rn, run a soft CSP demo, and stop without EE081.
SV660N Keypad Panel Status Codes
Published:
SV660N 5-digit keypad: decode _28ry / AL blink, and panel-as-read faults (E6200, E6400, EE083) mapped to CoE 0x603F/0x203F.
sudo
Give AI Agents Sudo with SUDO_ASKPASS
Published:
When an agent cannot type a sudo password into a TTY, a short zenity askpass helper unlocks a stable sudo -A workflow.
suspend
Dell Latitude 5501 Linux Deep Sleep Experiment
Published:
I tried to reduce suspend battery drain on my Dell Latitude 5501 running Ubuntu 24.04.
sv660n
SV660N + MS1 from Scratch: EtherCAT, ROS 2, and a Smooth First Spin
Published:
Fresh Ubuntu 24.04 to a smooth SV660N/MS1 spin: wire the holding brake 24 V, build IgH with –disable-eoe, ROS 2 Jazzy + motor_drive, reach panel _88rn, run a soft CSP demo, and stop without EE081.
SV660N Keypad Panel Status Codes
Published:
SV660N 5-digit keypad: decode _28ry / AL blink, and panel-as-read faults (E6200, E6400, EE083) mapped to CoE 0x603F/0x203F.
terminal
Setting Up Jupyter Terminal Keyboard Shortcut
Published:
Learn how to quickly create a new terminal in Jupyter using a custom keyboard shortcut. This is especially useful for developers who frequently need to run shell commands while working in Jupyter notebooks.
troubleshooting
macOS 下清理应用状态修复 WeType 简繁切换残留问题
Published:
macOS 下遇到一个 WeType 的奇怪问题：切换到繁体输入后，再切回简体输入，有些字仍然会按繁体输出，例如 還、總、覆 这类结果会残留在简体模式里。
GitLab in Docker showed 502 after restart: root cause and fix
Published:
I ran into a GitLab outage in a Docker-based deployment where the web UI returned 502 Bad Gateway, even though the container itself was still running and even showed as healthy in docker ps.
tun
Fix Clash Verge TUN Mode on Ubuntu: operation not permitted
Published:
Clash Verge TUN mode is useful because it gives you system-wide proxying without configuring every application separately.
ubuntu
Set Dell Battery Charge Limits on Linux with cctk
Published:
| On Dell Latitude 5501, smbios-battery-ctl can read charge limits but cannot set them. Use Dell Command | Configure (cctk) to write Custom:50-80 to the EC. |
Disable Clash Verge Rev Auto Check Update on Ubuntu
Published:
Turn off Clash Verge Rev update checks by setting auto_check_update: false in verge.yaml — a setting the GUI does not expose.
Why ROS 2 Demands System Python (And How to Fix Virtual Environment Conflicts)
Published:
Standard Python virtual environments hide ROS 2 apt packages from colcon. Use –system-site-packages so pip stays isolated while builds can still import em, catkin_pkg, and friends.
How to Install Ubuntu 24.04 Real-Time Kernel (PREEMPT_RT) on a Dual-GPU Laptop
Published:
Install ubuntu-realtime on Ubuntu 24.04 with Intel + NVIDIA hybrid graphics: why apt stalls at 2%, why NVIDIA DKMS fails against PREEMPT_RT, how to finish dpkg, and how to restore nvidia-smi on the generic kernel only.
Add VS Code to the Nautilus Context Menu on Ubuntu
Published:
Use a Nautilus Python extension to put Open in VS Code on right-click for files, folders, and empty folder backgrounds.
Free Disk Space by Cleaning Stale Snap Revisions on Ubuntu
Published:
How I reclaimed about 2.8 GB from /var/lib/snapd/snaps on Ubuntu 24.04 by removing disabled Snap revisions and unused GNOME platform snaps.
Fixing llvmpipe on Ubuntu Wayland with Intel + NVIDIA Hybrid Graphics
Published:
How I diagnosed a misleading llvmpipe report on Ubuntu Wayland and fixed the real Xwayland/GLX fallback by updating Xwayland and Xorg core packages.
Fix Clash Verge TUN Mode on Ubuntu: operation not permitted
Published:
Clash Verge TUN mode is useful because it gives you system-wide proxying without configuring every application separately.
Dell Latitude 5501 Linux Deep Sleep Experiment
Published:
I tried to reduce suspend battery drain on my Dell Latitude 5501 running Ubuntu 24.04.
Ubuntu 下给微信添加显示/隐藏快捷键
Published:
Linux 版微信在 Ubuntu 中没有内置的显示/隐藏窗口快捷键，可以用 xdotool 和 GNOME 自定义快捷键实现一个类似的切换功能。
Fixing XWayland High CPU Spikes on Ubuntu 24.04 with Intel + NVIDIA Hybrid Graphics
Published:
How installing the proprietary NVIDIA driver fixed repeated XWayland CPU spikes when launching Electron and Chromium apps on an Ubuntu 24.04 Intel + NVIDIA hybrid laptop.
ux
GRUB’s GRUB_DEFAULT and GRUB_SAVEDEFAULT: Flexible but Confusing Design
Published:
GRUB splits reading and writing the saved boot entry across GRUB_DEFAULT and GRUB_SAVEDEFAULT. That flexibility helps admins and automation, but it exposes mechanism instead of user intent—and nested configfile menus can silently break remember-last-selection.
venv
Why ROS 2 Demands System Python (And How to Fix Virtual Environment Conflicts)
Published:
Standard Python virtual environments hide ROS 2 apt packages from colcon. Use –system-site-packages so pip stays isolated while builds can still import em, catkin_pkg, and friends.
vfs
VFS 签证预约系统访问慢，可以先检查 DNS
Published:
在中国使用 VFS 签证预约系统时，如果 Cloudflare 验证加载很慢、页面经常卡死或登录被临时锁定，可以先尝试把 DNS 改成 1.1.1.1 和 8.8.8.8。
virtualization
Command-Line Scripts for Virtual Machine Management with Libvirt/KVM/QEMU
Published:
A collection of command-line scripts and tools for managing virtual machines using Libvirt, KVM, and QEMU, covering common VM operations, automation, and best practices.
visa
VFS 签证预约系统访问慢，可以先检查 DNS
Published:
在中国使用 VFS 签证预约系统时，如果 Cloudflare 验证加载很慢、页面经常卡死或登录被临时锁定，可以先尝试把 DNS 改成 1.1.1.1 和 8.8.8.8。
vm-management
Command-Line Scripts for Virtual Machine Management with Libvirt/KVM/QEMU
Published:
A collection of command-line scripts and tools for managing virtual machines using Libvirt, KVM, and QEMU, covering common VM operations, automation, and best practices.
vscode
Add VS Code to the Nautilus Context Menu on Ubuntu
Published:
Use a Nautilus Python extension to put Open in VS Code on right-click for files, folders, and empty folder backgrounds.
VS Code Codex Extension UI Freeze May Be Caused by Missing Shell Environment
Published:
Sometimes the Codex extension in VS Code can get stuck even though the Codex CLI still works normally.
wayland
Fixing llvmpipe on Ubuntu Wayland with Intel + NVIDIA Hybrid Graphics
Published:
How I diagnosed a misleading llvmpipe report on Ubuntu Wayland and fixed the real Xwayland/GLX fallback by updating Xwayland and Xorg core packages.
Fixing XWayland High CPU Spikes on Ubuntu 24.04 with Intel + NVIDIA Hybrid Graphics
Published:
How installing the proprietary NVIDIA driver fixed repeated XWayland CPU spikes when launching Electron and Chromium apps on an Ubuntu 24.04 Intel + NVIDIA hybrid laptop.
Ubuntu 下给微信添加显示/隐藏快捷键
Published:
Linux 版微信在 Ubuntu 中没有内置的显示/隐藏窗口快捷键，可以用 xdotool 和 GNOME 自定义快捷键实现一个类似的切换功能。
weixin
Ubuntu 下给微信添加显示/隐藏快捷键
Published:
Linux 版微信在 Ubuntu 中没有内置的显示/隐藏窗口快捷键，可以用 xdotool 和 GNOME 自定义快捷键实现一个类似的切换功能。
wetype
macOS 下清理应用状态修复 WeType 简繁切换残留问题
Published:
macOS 下遇到一个 WeType 的奇怪问题：切换到繁体输入后，再切回简体输入，有些字仍然会按繁体输出，例如 還、總、覆 这类结果会残留在简体模式里。
windows
Codex CLI 0.119.0 on Windows: prefix_rule for git is not usable
Published:
Quick note from testing codex cli 0.119.0 on Windows: prefix_rule was not practical for allowing common git commands in a reusable way.
Install OpenSSH Server on Windows from the Win32-OpenSSH release zip
Published:
Quick notes for setting up the Windows OpenSSH server from the OpenSSH-Win64.zip package.
wireguard
Run WireGuard on Apple Silicon macOS with wg-quick and launchd
Published:
Quick notes for running a WireGuard tunnel on an Apple Silicon Mac with wg-quick and launchd.
workflow
Syncing Two Git Machines Over LAN Without a Central Server
Published:
Sometimes the normal Git server is temporarily unavailable, but you still need to move work between two machines on the same local network.
A Professional Git Worktree Workflow with a Bare Repository
Published:
If you regularly switch between branches, keep separate runtime environments, or want AI agents to work without disturbing your main checkout, a bare repository plus git worktree is one of the cleanest setups.
worktree
Syncing Two Git Machines Over LAN Without a Central Server
Published:
Sometimes the normal Git server is temporarily unavailable, but you still need to move work between two machines on the same local network.
A Professional Git Worktree Workflow with a Bare Repository
Published:
If you regularly switch between branches, keep separate runtime environments, or want AI agents to work without disturbing your main checkout, a bare repository plus git worktree is one of the cleanest setups.
xdotool
Ubuntu 下给微信添加显示/隐藏快捷键
Published:
Linux 版微信在 Ubuntu 中没有内置的显示/隐藏窗口快捷键，可以用 xdotool 和 GNOME 自定义快捷键实现一个类似的切换功能。
xwayland
Fixing llvmpipe on Ubuntu Wayland with Intel + NVIDIA Hybrid Graphics
Published:
How I diagnosed a misleading llvmpipe report on Ubuntu Wayland and fixed the real Xwayland/GLX fallback by updating Xwayland and Xorg core packages.
Fixing XWayland High CPU Spikes on Ubuntu 24.04 with Intel + NVIDIA Hybrid Graphics
Published:
How installing the proprietary NVIDIA driver fixed repeated XWayland CPU spikes when launching Electron and Chromium apps on an Ubuntu 24.04 Intel + NVIDIA hybrid laptop.
zenity
Give AI Agents Sudo with SUDO_ASKPASS
Published:
When an agent cannot type a sudo password into a TTY, a short zenity askpass helper unlocks a stable sudo -A workflow.