Summary of Bluetooth Development Experience - Automatic Pairing

Scene: Control side - ordinary mobile phone; Controlled side - XX device (no screen, no user operation, system privileges) There are two ways to find a device when Bluetooth is on: search and specify a mac.Searching for Bluetooth devices with the search function involves the concept of "visibility". Bluetooth ...

Posted on Tue, 14 Jul 2020 11:33:30 -0400 by radhoo

Installation and configuration of Ubuntu firewall

Ubuntu Install UFW firewall sudo apt-get install ufw For general users, only the following settings are required: sudo apt-get install ufw sudo ufw enable sudo ufw default deny The above three commands are safe enough. If you need to open some services, you can use sudo ufw allow. Enable sudo ufw enable sudo ufw default deny #Aft ...

Posted on Fri, 10 Jul 2020 12:13:14 -0400 by mckinney3

Some differences between Synchronized decorating method and code block at the bottom

Article catalog Decorated code block Modify instance method Modifying static methods summary Decorated code block The above example: public class SyncCodeBlock { public int i; public void syncTask(){ //Sync codebase synchronized (this){ i++; } } } Compile with j ...

Posted on Sat, 27 Jun 2020 02:14:36 -0400 by bobby4

linux raw socket grabs network packets

Packet capturing based on linux 1, Get data When we do network security or data detection work, we often use packet capturing. Familiar tools include tcpdump, wireshark, etc. Here we introduce how to use C program raw socket to grab IP link layer packets on linux system. First of all, we are familia ...

Posted on Sat, 20 Jun 2020 03:21:55 -0400 by bamfon

TSO process analysis

1. TSO(transimit segment offload) is for tcp. It refers to the ability of the protocol stack to offload the tcp segment operation to the hardware, which needs the support of the hardware. When the network card has TSO capability, the upper layer protocol stack can directly send a packet over MTU, and ...

Posted on Sat, 20 Jun 2020 01:21:48 -0400 by Nicholas Reed

Using nsq to generate pdf service with puppeter under node (eggjs)

The last article said ctx.service.pdf.index.generate(data) method is the core business method. Call service/pdf/ in root directory in egg index.js The generate method under. Let's talk about eggjs. Official website address: https://eggjs.org/zh-cn/basic.... Get to know eggjs Egg.js Born for enterprise framework and application, we should all ...

Posted on Fri, 19 Jun 2020 06:35:49 -0400 by snake310

Use Node.js Drive Redis to implement a message queue!

Write at the beginning Recently Devops and Micro Front End have written almost the same, I started reviewing the knowledge of the back end, I wanted to write this article before, and finally fell to the ground If you want to join the front-end communication group, you can contact me at the end to join Official Start Mac|Linux recommended for ...

Posted on Tue, 16 Jun 2020 22:14:17 -0400 by parkej60

Wechat code scanning payment (detailed code)

Wechat code scanning payment Recently, when the project was rebuilt, she was responsible for the payment module. WeChat scan code payment (NATIVE) and Alipay scan code payment were also the first contact. Although it was written out according to official documents and some blogs, there were many proble ...

Posted on Mon, 15 Jun 2020 04:48:05 -0400 by ams007

linux basic services (DHCP)

DHCP Article catalog DHCP What is DHCP How DHCP works Three allocation mechanisms of DHCP Set up DHCP What is DHCP DHCP, the dynamic host configuration protocol, is a local area network protocol. It uses UDP protocol to work. It automatically assigns IP addresses to internal local area netwo ...

Posted on Tue, 09 Jun 2020 02:54:58 -0400 by Volte6

A complete manual for beginners to build ngrok

With all due respect, programmers who can't even be lazy are really tired~ Some time ago, WeChat official account was developed. WeChat official account was required to configure public domain name. The local ones don't work. Set up the ngrok little white manual Mapping local services to the public n ...

Posted on Tue, 09 Jun 2020 00:40:28 -0400 by intercampus