static int __init my_init(void)
{
int count = 32;
char buf1[32], buf2[32];
my_fun(buf1, buf2, count, NULL);
return 0;
}
int main(int argc, char* argv[])
{
my_fun(10); // 这是直接调用my_fun函数
my_fun_pointer = my_fun; // 将my_fun函数的地址赋给my_fun_pointer变量
my_fun_pointer(20); // 这是通过函数指针变量my_fun_pointer来调用my_fun函数的。
return 0;
}
int main()
{
struct sockaddr_in sin;
struct sockaddr_in cin;
int l_fd;
int c_fd;
socklen_t len;
char buf[MAX_LINE];
char addr_p[INET_ADDRSTRLEN];
int port = 8000;
int n;
bzero(&sin, sizeof(sin));
sin.sin_family = AF_INET;
sin.sin_addr.s_addr = INADDR_ANY;
sin.sin_port = htons(port);
if ( (l_fd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
perror("fail to create socket");
exit(1);
}
if (bind(l_fd, (struct sockaddr *)&sin, sizeof(sin)) == -1) {
perror("fail to bind");
exit(1);
}
if (listen(l_fd, 10) == -1) {
perror("fail to listen");
exit(1);
}
printf("waiting ...\n");
while (1)
{
if ((c_fd = accept(l_fd, (struct sockaddr *)&cin, &len)) == -1) {
perror("fail to accept");
exit(1);
}
n = my_read(c_fd, buf, MAX_LINE);
if (n == -1) {
exit(1);
} else if (n == 0) {
printf("the connect has been closed\n");
close(c_fd);
continue;
}
inet_ntop(AF_INET, &cin.sin_addr, addr_p, sizeof(addr_p));
printf("client IP is %s, port is %d\n", addr_p, ntohs(cin.sin_port));
printf("contens is : %s\n", buf);
my_fun(buf);
n = write(c_fd, buf, n);
if (n == -1) {
exit(1);
}
if (close(c_fd) == -1) {
perror("fail to close");
exit(1);
}
}
return 0;
}
int main()
{
struct sockaddr_in sin;
struct sockaddr_in cin;
int s_fd;
int port = 8000;
socklen_t addr_len;
char buf[MAX_LINE];
char addr_p[INET_ADDRSTRLEN];
int n;
bzero(&sin, sizeof(sin));
sin.sin_family = AF_INET;
sin.sin_addr.s_addr = INADDR_ANY;
sin.sin_port = htons(port);
s_fd = socket(AF_INET, SOCK_DGRAM, 0);
if (s_fd == -1) {
perror("fail to create socket");
exit(1);
}
if (bind(s_fd, (struct sockaddr *)&sin, sizeof(sin)) == -1) {
perror("call to bind");
exit(1);
}
while (1)
{
addr_len = sizeof(sin);
n = recvfrom(s_fd, buf, MAX_LINE, 0, (struct sockaddr *)&cin, &addr_len);
if (n == -1) {
perror("fail to receive\n");
exit(1);
}
inet_ntop(AF_INET, &cin.sin_addr, addr_p, sizeof(addr_p));
printf("client IP is %s, port, is %d\n", addr_p, ntohs(cin.sin_port));
printf("content is : %s\n", buf);
my_fun(buf);
n = sendto(s_fd, buf, n, 0, (struct sockaddr *)&cin, addr_len);
if (n == -1) {
perror("fail to send");
exit(1);
}
}
if (close(s_fd) == -1) {
perror("fail to close");
exit(1);
}
return 0;
}
int main(void)
{
struct sockaddr_in sin;
struct sockaddr_in cin;
int l_fd;
int c_fd;
socklen_t len;
char buf[MAX_LINE];
char addr_p[INET_ADDRSTRLEN];
int port = 8000;
int n;
bzero(&sin,sizeof(sin)); // clear address struct
sin.sin_family = AF_INET;
sin.sin_addr.s_addr = htonl(INADDR_ANY);
sin.sin_port = htons(port);
l_fd = socket(AF_INET,SOCK_STREAM,0); // tcp
bind(l_fd, (struct sockaddr *) &sin, sizeof(sin));
listen(l_fd,10);
printf("waiting ...\n");
while(1)
{
c_fd = accept(l_fd, (struct sockaddr *) &cin, &len);
n = read(c_fd,buf,MAX_LINE);
inet_ntop(AF_INET,&cin.sin_addr,addr_p,sizeof(addr_p));
printf("client IP is %s port is %d\n",addr_p,1);//ntohs(c_fd.sin_port));
printf("content is :%s\n", buf);
my_fun(buf);
write(c_fd,buf,n);
close(c_fd);
}
if(close(l_fd) == -1)
{
perror("fail to close");
exit(1);
}
return 0;
}
int main(int argc,char *argv[])
{
struct sockaddr_in sin;
struct sockaddr_in cin;
int l_fd;
int c_fd;
socklen_t len;
char buf[MAX_LINE];
char addr_p[INET_ADDRSTRLEN];
int port = 8000;
int n;
bzero(&sin,sizeof(sin));
sin.sin_family = AF_INET;
sin.sin_addr.s_addr = INADDR_ANY;
sin.sin_port = htons(port);
l_fd = socket(AF_INET,SOCK_STREAM,0);
bind(l_fd,(struct sockaddr *)&sin,sizeof(sin));
listen(l_fd,10);
printf("waiting ...\n");
while (1)
{
c_fd = accept(l_fd,(struct sockaddr *)&cin,&len);
n = read(c_fd,buf,MAX_LINE);
inet_ntop(AF_INET,&cin.sin_addr,addr_p,sizeof(addr_p));
printf("client IP is %s, port is %d\n",addr_p,ntohs(cin.sin_port));
printf("content is : %s\n",buf);
my_fun(buf);
write(c_fd,buf,n);
close(c_fd);
}
return 0;
}
int main (void)
{
printf("my_fun(2.2,0)= %f\n",my_fun(2.2,0));
printf("my_fun(2.2,1)= %f\n",my_fun(2.2,1));
printf("my_fun(2.2,2)= %f\n",my_fun(2.2,2));
printf("my_fun(2.2,3)= %f\n",my_fun(2.2,3));
printf("my_fun(2.2,4)= %f\n",my_fun(2.2,4));
printf("my_fun(2.2,5)= %f\n",my_fun(2.2,5));
printf("my_fun(2.2,6)= %f\n",my_fun(2.2,6));
printf("my_fun(2.2,7)= %f\n",my_fun(2.2,7));
printf("my_fun(2.2,8)= %f\n",my_fun(2.2,8));
printf("my_fun(2.2,9)= %f\n",my_fun(2.2,9));
printf("my_fun(2.2,10)= %f\n",my_fun(2.2,10));
printf("\n\n\n\n");
double margin =0.0; //差額
int n = 2;
double big,small;
do{
printf("----------------------\n");
if(my_fun(2.2,n)>my_fun(2.2,n-1)){
margin = my_fun(2.2,n) - my_fun(2.2,n-1);}
else{
margin = my_fun(2.2,n-1) - my_fun(2.2,n) ;
}
printf("n=%d n-1=%d margin=%f \n",n,n-1,margin);
n++;
} while (margin >=0.0001) ;
printf("\n\n當n等於%d時my_fun(2.2,n-1)與my_fun(2.2,n)的差額小於0.0001\n\n",n-1);
system("pause");
return 0;
}
int main(void)
{
int lfd, cfd;
time_t staletime; /* 测试客户端进程的时间 */
struct sockaddr_un un_addr;
struct stat statbuf;
char buf[MAX];
int len, n;
if(init(&lfd, PATH) == -1) /* 调用初始化函数，创建监听套接字，并且开始监听 */
exit(1);
while(1){/* 服务器程序多半是死循环 */
len = sizeof(struct sockaddr_un);
/* 处理一个连接，创建连接套接字，得到客户端进程的套接字文件路径
* 并将其保存在un_addr结构中，注意这里使用sockaddr_un结构的大小
*/
if ((cfd = accept(lfd, (struct sockaddr *)&un_addr, &len)) == -1){
perror("fail to accept");
exit(1);
}
/* 得到客户端文件的路径，并且设置结束符 */
len -= offsetof(struct sockaddr_un, sun_path);
un_addr.sun_path[len] = '\0';
/* 得到文件爱你的状态信息，为了验证客户端进程的通信时间
* 客户端进程如果长期没有修改通信用的套接字文件，说明该客户端有可能已经结束通信
* 下面分别验证文件的权限和修改时间，这些操作并不是必须的
* 但是出于程序的完整性考虑，这些操作还是必要的
*/
if (stat(un_addr.sun_path, &statbuf) == -1) {
perror("fail to get status");
exit(1);
}
/* 检查文件的权限，通信用的套接字文件的权限必须是"rwx------"
* 也就是说之用所有者用户可以有读、写和执行该文件的权限，其他用户没有
* 这说明Unix域套接字只能用于同一用户的进程之间的通信
*/
if ((statbuf.st_mode & (S_IRWXG | S_IRWXO)) || (statbuf.st_mode & S_IRWXU) != S_IRWXU) {
printf("wrong permissions\n");
exit(1);
}
/* 检查套接字文件的更新时间，超过三十秒钟未作访问和修改
* 说明客户端进程可能已经断开了连接，关闭连接套接字，结束连接
*/
staletime = time(NULL) - STALE;
if (statbuf.st_atime < staletime || statbuf.st_ctime < staletime || statbuf.st_mtime < staletime){
printf("client is too old\n");
close(cfd);
break;
}
/* 删除客户端的套接字文件
* 该套接字文件由客户端进程在调用bind函数进行套接字绑定的时候生成
*/
if(unlink(un_addr.sun_path) == -1){
perror("fail to unlink");
exit(1);
}
my_fun(buf); /* 调用大小写转换函数 */
if(write(cfd, buf, n) == -1){ /* 将转换后的字串发给客户端进程 */
perror("fail to write");
exit(1);
}
close(cfd); /* 通讯结束，关闭套接字，准备下一次通信 */
}
/* 删除服务器进程的套接字文件 */
if(unlink(PATH) == -1){
perror("fail to unlink");
exit(1);
}
close(lfd);
return 0;
}
