fieldbus communication

The nameless pipe communication in the previous article is the communication between the parent-child process, which restricts the communication between the processes, so that there is a well-known pipeline, which can make communication between different processes, the famous pipe can be indicated by specifying the pat

Shared Memory: It is the most efficient communication mechanism in the System V version that allows multiple processes to share the same address space, and if a process modifies that address space, other processes that share the address space can see it at the same time, but it does not provide synchronization and mutex. The general combination of semaphores to achieve synchronization between the process of mutual exclusion.Create shared memory: int s

High-performance communication library-zeroMQ, high-performance communication-zeromq First, let me introduce ZMQ (full name: ZeroMQ ): Official: "ZMQ (ZMQ for short) is a simple and easy-to-use transmission layer, a socket library like a framework. It makes Socket programming simpler, more concise, and more efficient. Is a message processing queue library that can be elastically scaled between multiple thre

Socket connection and HTTP connectionSince the socket connection is usually a TCP connection, once the socket connection is established, the communication parties can start sending data content to each other until the two sides are disconnected. However, in real network applications, the client-to-server communication often needs to traverse multiple intermediary nodes, such as routers, gateways, firewalls,

WM_COPYDATA inter-process communication scheme, wm_copydata Communication WM_COPYDATA is used in two companies to implement inter-process communication. Procedure: 1. process A starts process B through ShellExecute and passes the hWndA (strongly converted to int value) of the window handle used for communication to

Bowen viewpoint lecture hall38Period Plot the workplace-the most economical Graphic Communication A communication capability that can improve the competitiveness of the workplace In the workplace, communication is an important skill! If you cannot express or be understood, I am afraid you will not be able to feel sorry for it. In enterprise management practices

3.4 use wm_copydata for Message Communication For a small amount of data, wm_copydata can be used for convenient communication. Because sendmessage () is blocked, only sendmessage () can be returned if the receiver responds to the message. Otherwise, it will be blocked all the time. Therefore, for a large amount of data, the use of sendmessage () can easily lead to false window death.3.4.1 how to implement

　　background: The recent project uses a piece of industrial board, the board hardware and the host computer through the UDP communication, but the manufacturers only provide C # demo, and the corresponding driver commands encapsulated as DLL dynamic library. Another project team wants to be able to drive this industrial board under the Android platform, I have previously written some of the underlying drivers, but all received through the serial port

There are three modes of communication in the current network: unicast, broadcast, multicast (multicast), which has the advantage of multicast and broadcast at the latest, and has the most development foreground.One, unicast:The "one-on" communication mode between hosts, switches and routers in the network are forwarded to the data only and not replicated. If 10 clients require the same data, the server nee

This article takes the Visual C + + data acquisition and the serial communication measurement and control application actual combat as the reference tutorialThis article is suitable for VC + + Serial Communication IntroductionOne, page layout and add controls1, install the vs2010.2, create a new MFC project based on VC + + CommNote: Click OK, then next, to change the application type to dialog base, then ne

Microsoft Communication Framework practice-main concepts and communication framework practice Windows Communication Foundation (WCF) is a series of application frameworks developed by Microsoft to support data Communication. It is a cross-platform security, reliable, and transactional solution. It is a web service ,. n

Communication between a thread DWORD WINAPI firstthread (void *p) {messageboxa (0, "1", "1", 0); printf ("1th thread execution complete \ n"); SetEvent (event[0]);//Send event signal return 0; } DWORD WINAPI secondthread (void *p) {WaitForSingleObject (event[0], INFINITE);//wait for the event signal to appear, perform the next messageboxa (0, "2", " 2 ", 0); printf ("2nd thread execution complete \ n"); return 0; } void Main () {//security_attributes,

Winform serial communication platform, winform Serial Communication Next to the last card reading, you need to make a weighbridge read. The following figure shows how to read the lbs. The weighbridge always sends data to the serial port, so it is necessary to intercept the data to determine whether the data is legal and then calculate the result. I encountered a small problem. I will introduce it at the end

Linux inter-process communication: Message Queue and linux Process Communication queue I. Features of Message Queue 1. A message queue is a linked list of messages in a specific format. It is stored in the memory and identified by the Message Queue identifier.2. A Message Queue allows one or more processes to write and read messages to it.3. Both pipelines and named pipelines are

Message Queue for Linux Process Communication and linux Process Communication queue Based on the following ideas, this article first elaborates on the message queue mechanism from a macro perspective, then describes the mechanism using the specific code as an example, and finally tries to think about the potential application of the communication mechanism. Mess

Java implements multi-threaded socket communication technology, and ocket Communication Technology In the previous example, we use the following code: Package com.test.net; import java. io. dataInputStream; import java. io. inputStream; import java.net. serverSocket; import java.net. socket; public class EchoServer {/*** print all client output */@ SuppressWarnings ("deprecation") public static void main (

Synchronous communication between threads and synchronous communication between threads We all know that the thread code in java can be written as follows: new Thread(new Runnable() {@Overridepublic void run() {// TODO Auto-generated method stub}}).start();Under multi-thread startup, the running between threads will be switched randomly. Generally, we may need to switch between threads in an orderly manner

Simple analysis Ucenter member Synchronous login Communication principle, ucenter communication principle 1, the user login discuz, through the logging.php file function Uc_user_login to post data verification, that is, username and password to verify. 2. If the validation succeeds, the function uc_user_synlogin in the client.php file under Uc_client will be called, in which uc_api_post (' user ', ' synlog

Message communication messagesMessages are an important way of interprocess communication, usually made up of both the client and server side. The server creates a message queue with a specific key value, populates the message queue with the message and data type to be sent according to the agreed message format. On the client side, the corresponding data is received according to the known key value and the

Pipe Introduction Pipelines are a way of interprocess communication in Linux, which connects the output of a program directly to the input of another program (in fact, I prefer to liken the pipe to the pipe of a rural land). The main pipeline of Linux includes two kinds: nameless pipe and famous pipe. This section mainly talks about the nameless pipeline, first introduces these two pipes. (the feature is very important!) ） 1, Nameless pipe The name