Linux Networking
Read guide Sending HTTP POST Data from a Client and Returning Server Responses via Netcat
Send HTTP POST data from client tools (curl, Python) and return custom JSON responses using Netcat over a specific port on Linux.
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Linux Kernel
Read guide Bi-Directional Communication Between User-Space and Linux Kernel via Netlink Sockets
Learn bi-directional user-space to Linux kernel communication using Netlink sockets (AF_NETLINK) with full C kernel module and user client examples.
Linux Networking
Read guide Listening on Specific Port Numbers with Netcat to Receive HTTP POST Requests
Listen on a specific port using Netcat (nc) to inspect incoming HTTP POST messages, webhooks, JSON payloads, and log headers in Linux.
Linux Host, Ubuntu, SysAdmin
Read guide Fix: no permissions (user in plugdev group; are your udev rules wrong?)
Resolve 'no permissions (user in plugdev group; are your udev rules wrong?)' error on Linux by configuring /etc/udev/rules.d/51-android.rules.
Ubuntu Applications
Read guide Fix: Chrome Error "Something Went Wrong When Opening Your Profile" on Linux
Fix Chrome error 'Something went wrong when opening your profile' on Linux by removing SQLite lock files, fixing permissions, and restoring data.
Linux Networking
Read guide Scanning and Listing Available Wi-Fi Networks in Linux: nmcli, iw, and iwlist
Scan and list available Wi-Fi networks in Linux using nmcli, iw, and iwlist. Learn BSSID, SSID, RSSI signal strength, and channel parsing.
Linux
Read guide Fix: error: package android.support.v7.app does not exist / AppCompatActivity cannot be resolved
Resolve 'error: package android.support.v7.app does not exist' and 'cannot resolve symbol AppCompatActivity' by migrating to AndroidX in Gradle.
Scripting and Automation
Read guide Automate Social Media Updates from Your Website Using Open-Source Tools and Webhooks
Automate social media posts from your website RSS feed using open-source tools like n8n, Huginn, and custom Node.js webhook bots.
Linux
Read guide Java UDP Socket Programming: DatagramSocket and DatagramPacket Client-Server Guide
Master Java UDP socket programming: complete client-server code using DatagramSocket and DatagramPacket, packet buffering, and MTU mechanics.