select function

Asynchronous nonblocking sockets avoid the reception of dead loops, but the software experience is still poor. The reason, the software in the instructions to send, receive,An unreasonable way to do this is to call the receive function immediately

Fd_set is a set of file descriptors (Fd,file descriptor) that represents an FD with one.The system provides 4 macros to describe the descriptor operation:#include #include Set file description descriptor bits in Fdset corresponding to the file

The Select () mechanism provides a FD_SET data structure, which is actually a long array in which each element of an array can be contacted with an open file handle (whether it is a socket handle or another file or a named pipe or device handle),

Transferred from: http://www.linuxidc.com/Linux/2011-03/33022.htmIn fact, I have just started to do not know how to write the driver, what do not understand, only know I need to do the project in the process of learning, so, I found myself a about

1. I/O modelThere are five kinds of I/O models under UNIXA. Blocking I/OB. Non-blocking I/OC. I/O multiplexing (SELECT and poll)D. Signal-driven I/O (Sigio)E. Asynchronous I/O (posix.1 aio_ series functions)1). blocking I/O modelThe application

In detail before JDK 1.4, Java IO Operations were concentrated in the Java.io package and were based on the streaming synchronization (blocking) API. For most applications, such APIs are easy to use, however, some applications with high performance

Formatted read/write: # Include Int printf (const char * format,...); // equivalent to fprintf (stdout, format ,...); Int scanf (const char * format ,...); Int fprintf (FILE * stream, const char * format,...); // The intermediate parameter is the

Synchronous, asynchronous, blocking, and non-blocking. when these network I/O terms are combined, it will inevitably confuse programming beginners, here we will summarize the Python instances of the network I/O model and select model for

Io is the input/output in the computer, that is, input and output. Because the program and runtime data resides in memory and is executed by the CPU, an ultra-fast compute core, where the data is exchanged, usually a disk, a network, and so on,

(The following comes from the web and its own summary, thanks again for the insights provided by the great gods on the Web)Before exploring Select poll Epoll We first need to know what is called multiplexing:Come down and explore why multiplexing is

1 Low efficiency of SELECTThe efficiency of the Select/poll function is low, there are two main reasons:(1) All file descriptors need to be searched after calling the Select function(2) You need to pass monitoring object information to the function

Chapter 12th Concurrent Programming the first section of the process-based concurrency programming the simplest way to construct a concurrency program: processCommon functions are as follows: Fork Exec Waitpid Section II

The Select function is used in non-blocking, when a socket or a set of sockets is signaled, the system provides a select function to implement the multiplexed input/output model, the prototype:int select (int maxfd,fd_set *rdset,fd_set *wrset,fd_set

thinkphp Framework Security Implementation Analysis, thinkphp framework implementation Thinkphp Framework is one of the most popular PHP frameworks in China, although it is not comparable with those of foreign countries, but the advantage is that,

Python 3: select-based event driver, pythonselect The basic principle of this function is that the select/epoll function will continuously poll all the sockets in charge. When a socket has data, it will notify the user process. Its Process When a

I. synchronous and asynchronousSynchronous/asynchronous, which are notifications of messages1. ConceptsA. SynchronizationThe so-called synchronization means that when a function call is sent, the call will not return until the result is not obtained.

Select is important in Socket programming. It can monitor changes in file descriptors that we need to monitor-read/write or exceptions.The Select Function Format (Berkeley socket programming in Unix System, which is slightly different from that in

See chapter 5 of Windows Network Programming. To consolidate knowledge and drive problems, check knowledge points. Select model in Windows 1. What is the role of the select model? You can determine whether data exists on the specified socket and

Analysis of five IO models and five I/O models Directory:1. Basics2. I/O model2.1 Blocking I/O model2.2 Non-Blocking I/O model2.3 I/O Multiplexing Model2.4 Signal-driven I/O model2.5 Asynchronous I/O model2.6 distinction between synchronous IO and

Recently, I encountered a problem. For socket communication in blocking mode, if you want to implement device command control, the buffer zone cannot contain information not retrieved from the previous communication before entering the command