#include <stdlib.h>#include <stdio.h>#include <assert.h>#include <unistd.h>#include <sys/types.h>#include <sys/epoll.h>#include <fcntl.h>#include <sys/socket.h>#include <netinet/in.h>#include <arpa/inet.h>#include <string.h>static const char* request = "POST HTTP/1.1\r\n";int setnonblocking( int fd ){int old_option = fcntl( fd, F_GETFL );int new_option = old_option | O_NONBLOCK;fcntl( fd, F_SETFL, new_option );return old_option;}void addfd( int epoll_fd, int fd ){epoll_event event;event.data.fd = fd;event.events = EPOLLOUT | EPOLLET | EPOLLERR;epoll_ctl( epoll_fd, EPOLL_CTL_ADD, fd, &event );setnonblocking( fd );}bool write_nbytes( int sockfd, const char* buffer, int len ){int bytes_write = 0;printf( "write out %d bytes to socket %d\n", len, sockfd );while( 1 ){bytes_write = send( sockfd, buffer, len, 0 );if ( bytes_write == -1 ){return false;}else if ( bytes_write == 0 ){return false;}len -= bytes_write;buffer = buffer + bytes_write;if ( len <= 0 ){return true;}} }bool read_once( int sockfd, char* buffer, int len ){int bytes_read = 0;memset( buffer, '\0', len );bytes_read = recv( sockfd, buffer, len, 0 );if ( bytes_read == -1 ){return false;}else if ( bytes_read == 0 ){return false;}printf( "read in %d bytes from socket %d with content: %s\n", bytes_read, sockfd, buffer );return true;}void start_conn( int epoll_fd, int num, const char* ip, int port ){int ret = 0;struct sockaddr_in address;bzero( &address, sizeof( address ) );address.sin_family = AF_INET;inet_pton( AF_INET, ip, &address.sin_addr );address.sin_port = htons( port );for ( int i = 0; i < num; ++i ){sleep( 1 );int sockfd = socket( PF_INET, SOCK_STREAM, 0 );printf( "create 1 sock\n" );if( sockfd < 0 ){continue;}if ( connect( sockfd, ( struct sockaddr* )&address, sizeof( address ) ) == 0 ){printf( "build connection %d\n", i );addfd( epoll_fd, sockfd );}}}void close_conn( int epoll_fd, int sockfd ){epoll_ctl( epoll_fd, EPOLL_CTL_DEL, sockfd, 0 );close( sockfd );}int main( int argc, char* argv[] ){assert( argc == 4 );int epoll_fd = epoll_create( 100 );start_conn( epoll_fd, atoi( argv[ 3 ] ), argv[1], atoi( argv[2] ) );epoll_event events[ 10000 ];char buffer[ 2048 ];while ( 1 ){int fds = epoll_wait( epoll_fd, events, 10000, 2000 );for ( int i = 0; i < fds; i++ ){int sockfd = events[i].data.fd;if ( events[i].events & EPOLLIN ){if ( ! read_once( sockfd, buffer, 2048 ) ){close_conn( epoll_fd, sockfd );}struct epoll_event event;event.events = EPOLLOUT | EPOLLET | EPOLLERR;event.data.fd = sockfd;epoll_ctl( epoll_fd, EPOLL_CTL_MOD, sockfd, &event );}else if( events[i].events & EPOLLOUT ){if ( ! write_nbytes( sockfd, request, strlen( request ) ) ){close_conn( epoll_fd, sockfd );}struct epoll_event event;event.events = EPOLLIN | EPOLLET | EPOLLERR;event.data.fd = sockfd;epoll_ctl( epoll_fd, EPOLL_CTL_MOD, sockfd, &event );}else if( events[i].events & EPOLLERR ){close_conn( epoll_fd, sockfd );}}}}
，当你开展的事业从事的行动穷途末路大势已去的时候，
