socket programming in c

user process space copy (sendfile, splice and tee)Sendfile: it provides a mechanism to access the currently expanding Linux network stack. This mechanism is called "zero-copy", which can call "Transmission Control Protocol (TCP) the framework is directly transmitted from the host memory to the network card buffers, avoiding two context switches. For more information, see Splice and tee: The real concept behind splice is the concept of "random kernel buffer" exposed to the user space. "That is t

is not set, do not deliver.This interface is not delivered if the BIND port does not matchIf inaddr_any is not boundThe bind address and the destination address must match to deliver:That is to say, you must bind a broadcast address or bind inaddr_anyThirdIf your UDP calls connectThe source address and source port do not match and are not delivered.Otherwise deliver You can set the disable broadcast capability of one network card. Fannyth05-11-11, it seems that I want to reconsider the idea of

make the group broadcast text loop valid or invalid The IP_MREQ structure is defined in the header file: [code:1:63724de67f] struct Ip_mreq { struct in_addr imr_multiaddr;/* IP multicast address of Group */ struct IN_ADDR imr_interface;/* Local IP Address of interface */}; [/code:1:63724de67f] If the process is to be joined to a multicast group, use the Soket setsockopt () function to send the option. The option type is the IP_MREQ structure, it

the bottom to the top layer of a layer of unpacking. As for each layer, the format of the package is the format of the Protocol, mainly including the protocol header and data.Another famous soket is the application that is given to the kernel encapsulation data. We use Soket to write a program using only the parameters such as IP, port, and data.2.TCP protocolThe biggest difference between TCP and UDP is t

. println ("Close soket ");}If (CC! = NULL)Cc. onreceive (this, this. m_receive_data ); } } Catch (exception E){// An exception occurs. End the receiving thread.Cc. freeconnect (this );System. Out. println ("exception occurred, end receiving thread" + E. getmessage ());E. printstacktrace ();Break;}}} If (CC! = NULL ){Cc. freeconnect (this );System. Out. println ("exit and close soket ");}This. m_thread = NU

First, Zabbix3.2.6 use the self-brought template to monitor MySQLAdd Zabbix_agent Client Method: http://www.cnblogs.com/lei0213/p/8858269.htmlMySQL server-side configuration1, need to know:1, if you want to monitor MySQL or mariadb database, first you have to ensure that the normal operation of the server, so the first need to monitor this Linux server, if you add Linux monitoring, you can view my previous blog post.2, the database needs authorization. Mysql>grant USAGE on *. * to ' Zabbix ' @ '

In the socket, if created directly, only one user's request can be acceptedNeed to implement handle method in Socketserver, can implement multi-process concurrent access The Socketserver internally uses IO multiplexing and "multithreading" and "multi-process" to enable the socket service side to process multiple client requests concurrently. That is, when each client requests a connection to the server, the socket server is creating a "thread" or "process" dedicated to all requests from

1. Package management of the compilation of installation compilation of installation steps get the source code and unzip tarxvfpackage_version.tar. {GZ|BZ2|XZ}, expanded after directory name is usually package_version switch to the source directory cdpackage_ version Execute Configure script ./ configure (autoconf:configure script Check whether the compilation environment satisfies the compilation needs define which feature or feature is enabled at the time of the current program compi

a socket.The eintr was interrupted by the signal.Eagain This operation will block the process, but the socket for parameter s is not blocked.Insufficient buffer memory for ENOBUFS systemEnomem Core memory is lowEinval the parameter passed to the system call is incorrect. C language SendTo () function: data transfer via socketheader file: #include Definition function: int sendto (int s, const void * msg, int len, unsigned int flags, const struct SOCKADDR * to, int tolen); Functio

Of course, in accordance with their own preferences, of course, can also make soket services, but after all, PHP to do the service is not very good, and with shell monitoring, so it is better to use the URL rewrite The code is as follows Copy Code Location ~ ^ (. +\.md) (. *) {Rewrite. */md.php?file= $document _root$fastcgi_script_name last;} 4, in addition Finally, add a default page to the Nginx Web service

The Core Foundation Framework (corefoundation.framework) is a set of C language interfaces that provide basic data management and service functionality for iOS applications. The data that the framework supports for management and the services available are listed below: Group data types (arrays, collections, etc.) Program Package String Management Date and time management RAW Data Block Management Preference Management URL and Data flow operations Threads and Runloop Port and

use the configuration file for real deployment. In addition, in order to realize the connection between Nginx and Uwsgi, Soket is used to communicate between the two. In this section, we will use the UWSGI configuration file to improve the way Uwsgi is started. Suppose your program directory is/home/work/src/sites/testdjango1/testdjango/mysite We will allow Nginx to use 8077 port and UWSGI communication, please ensure that this port is not used by ot

Postrequest (String payload) Throws Httpserviceexception { PrintWriter out = null; BufferedReader in = null; URL url = null; Try { url = new URL (serviceurl); No Port? Use default port 80 int port = url.getport () Socket soket = new socket (Url.gethost (), port); out = new PrintWriter (Soket.getoutputstream ()); in = new BufferedReader (New InputStreamReader (Soket.getinputstream ())); } catch (Exception ex) { throw new Httpserviceexception ("Er

This article mainly introduces the example of writing a simple port scanner using Python. The article introduces the single-line and multi-thread implementation methods. If you need it, refer Single-threaded implementationThe single-thread implementation principle is relatively simple. Here we try to connect Soket to 3389. If the connection is successful, the port is opened. Otherwise, the remote service is not enabled. If you modify it, the Code is a

).　　Server: The component that is used to receive and respond to requests.0 under IIS, the Owin httpmodule "Dynamic" is registered in the IIS processing pipeline to receive processing HTTP requests by installing MICROSOFT.OWIN.HOST.SYSTEMWEB.0 in a custom host, by installing Microsoft.Owin.Host.HttpListener, explicitly open a soket based on the address and port in code to listen for requests. OwinHost.exe also uses this component to listen for request

1. If the socket is already in the established State (usually distinguished by the port number and flag ),Closesocket (usually does not close immediately and goes through the time_wait process) and wants to continue to reuse the socket:Bool breuseaddr = true;Setsockopt (S, sol_socket, so_reuseaddr, (const char *) amp; breuseaddr, sizeof (bool )); 2. If you want to force close a soket that is already in the connection status after you call closesocket

junior, and was rarely in school. The company's main business is to provide customers with enterprise website development. Due to the shortage of personnel, he is responsible for communicating with the customer, understanding the demand, talking with the customer about the price, webpage design, and background ASP program development. He has been trained a lot during this period of time. For various reasons, he has also changed many small and medium-sized companies in charge of development and

more information about the classes in the core data framework, seeCore data framework reference. Core foundation framework Core foundation framework(Corefoundation. FrameworkIs a set of C language interfaces that provide basic data management and service functions for iOS applications. The following lists the data and services that the Framework supports for management: Group data type (array, set, etc) Package String Management Date and Time Management Raw data block manag

From http://blog.csdn.net/diyagoanyhacker/article/details/7481637 Core foundation framework(Corefoundation. FrameworkIs a set of C language interfaces, which are IOS applications.ProgramProvides basic data management and service functions. The following lists the data and services that the Framework supports for management: Group data type (array, set, etc) Package String Management Date and Time Management Raw data block management Preference Management URL and data

Core foundation framework The core foundation framework is a set of C language interfaces that provide basic data management and service functions for iOS applications. The following lists the data and services that the Framework supports for management: Group data type (array, set, etc) Package String Management Date and Time Management Raw data block management Preference Management URL and data stream operations Thread and runloop Port and soket Co