fcntl

EPOLL-I/O Event Notification FacilityIn the Linux network programming, the long time uses the Select to do the event to trigger. In the new Linux kernel, there is a mechanism to replace it, that is epoll.The biggest benefit compared to Select,epoll

38 Network-related functions (vi)--live555 source Reading (iv) network 38 Network-related functions (vi)--live555 source Reading (iv) network Brief introduction Makesocketnonblocking and Makesocketblocking set interface

Remote illumination ExperimentExperimental Purpose:Realize remote lighting, through the GPRS self-debugging software to send information to complete the Intelligent furniture remote lighting experiment.1. Custom ARM SystemsUse Uboot data to bring

The source code is as follows:#include #include #include #include #include #include #include #include #include intTTY_FD;intMaxintAintb) {returnA>B?A:B;}intSet_opt (intFdintNspeed,intNBits,CharNevent,intNstop) {structTermios

I. Concepts and usage One problem:How do I create a full-duplex pipe? The direct method is, of coursePipeCreate two groups of pipelines twice, but is it easier? SocketpairMan socketpair: Socketpair-create a pair of connected sockets, the two sockets

In the previous article, we analyzed the process of registering a message with a sip service. Next we will analyze the process of processing an invite request.   From the handle_request_invite entry, the invite request processes the replace Request

Lists the functions that are called by the plug-in option system. 1. The setsockopt system call displays the options concentrated at the sol_socket level. The following is a prototype of setsockopt system call: The function copies data from the

The driver runs in the kernel space, and the application runs in the user space. The two cannot communicate directly. However, in actual application, when the device is ready, we want to notify the user that the program device is OK, The user

Because we finally need to implement this function on tiny210, and finally chose hotplug. Bytes. #ifndef HOSTPLUG_H#define HOSTPLUG_H#include #include #include #include #include #include #include #include #include #include #include #include static

Summary of select device timeout usage Currently, the common method for setting SOCKET connect timeout on each platform is to use select (). The specific method is as follows: 1. Establish socket; 2. Set the socket to non-blocking mode; 3. Call

Relationship between file descriptors and open files in LinuxRelationship between file descriptors and open files in LinuxGuideThe kernel uses file descriptor to access files. The file descriptor is a non-negative integer. When an existing file is

1) how to create an auto-increment field? A simple answer: a field declared as integer primary key will be automatically added. Here is a detailed answer: Starting from SQLite 2.3.4, if you declare a field in a table as integer primaryKey, so no

Linux serial port I/O mode As we all know, in Linux, all devices exist in the form of files, and the serial port is the same. Generally, I/O operations are implemented in two ways: blocking and non-blocking. The concept of "timeout" is actually a

/* set the open flag */ void setblock (int fd, int flags) { int val; If (val = fcntl (FD, f_getfl, 0) { perror ("fcntli get "); } Val | = flags; If (fcntl (FD, f_setfl, Val) { perror ("fcntl set"); }} /* clear the open flag */ void clrblock (int

Input and Output The I/O functions read and write data to and from files and devices. file I/O operations take place in text mode or binary mode. the Microsoft run-time Library has three types of I/O functions: Stream I/O functions treat data as a

I/O designed in this blog does not belong to the file I/O of ANSI C, and every function involved is a system call. It mainly involves the basic part of posix.1 I/O operations without caching.1. In the Linux kernel, only one identifier is required

/*************************************** **************************************** ************** Author: conowen @ Dazhong* E-mail: conowen@hotmail.com* Http://blog.csdn.net/conowen* Note: This article is original and only used for learning and

In the process of simultaneous operation of the same file by multiple processes, it is very easy to cause data confusion in the file, need to lock operation to ensure the integrity of the data, the file-based lock described here, called "File

Development test Environment: virtual machine centos,windows Network debugging assistantNon-blocking mode has 3 uses1. Three-time handshake to do other processing at the same time. Connect takes a round trip time, from a few milliseconds of LAN to a

All system calls that perform I/O operations refer to the open file as a file descriptor (a non-negative integer). File descriptors are used to represent all types of open files, including pipes, FIFO, sockets, terminals, devices, and normal files.