我来解决第四个问题吧,这是我写的串口通信的源码
#include
#include
#include
#include
#include
#include
#include
#include
#define PORT 5000 // The port which is communicate with server
#define LENGTH 256 // Buffer length
int main(int argc, char *argv[])
{
int sockfd; // Socket file descriptor
int num; // Counter of received bytes
char revbuf[LENGTH]; // Receive buffer
struct sockaddr_in remote_addr; // Host address information
/* Check parameters number */
if (argc != 2)
{
printf ("Usage: client HOST IP (ex: ./client 192.168.0.94).\n");
return (0);
}
/* Get the Socket file descriptor */
if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1)
{
printf("ERROR: Failed to obtain Socket Descriptor!\n");
return (0);
}
/* Fill the socket address struct */
remote_addr.sin_family = AF_INET; // Protocol Family
remote_addr.sin_port = htons(PORT); // Port number
inet_pton(AF_INET, argv[1], &remote_addr.sin_addr); // Net Address
bzero(&(remote_addr.sin_zero), 8); // Flush the rest of struct
/* Try to connect the remote */
if (connect(sockfd, (struct sockaddr *)&remote_addr, sizeof(struct sockaddr)) == -1)
{
printf ("ERROR: Failed to connect to the host!\n");
return (0);
}
else
{
printf ("OK: Have connected to the %s\n",argv[1]);
}
/* Try to connect the server */
while (strcmp(revbuf,"exit") != 0) // Check remoter command
{
bzero(revbuf,LENGTH);
num = recv(sockfd, revbuf, LENGTH, 0);
switch(num)
{
case -1:
printf("ERROR: Receive string error!\n");
close(sockfd);
return (0);
case 0:
close(sockfd);
return(0);
default:
printf ("OK: Receviced numbytes = %d\n", num);
break;
}
revbuf[num] = '\0';
printf ("OK: Receviced string is: %s\n", revbuf);
}
close (sockfd);
return (0);
}
#include
#include
#include
#include
#include
#include
#include
#include
#define PORT 5000 // The port which is communicate with server
#define BACKLOG 10
#define LENGTH 512 // Buffer length
int main ()
{ int sockfd; // Socket file descriptor
int nsockfd; // New Socket file descriptor
int num;
int sin_size; // to store struct size
char sdbuf[LENGTH]; // Send buffer
struct sockaddr_in addr_local;
struct sockaddr_in addr_remote;
char sendstr[16]= {"123456789 abcde"};
/* Get the Socket file descriptor */
if( (sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1 )
{
printf ("ERROR: Failed to obtain Socket Despcritor.\n");
return (0);
}
else
{
printf ("OK: Obtain Socket Despcritor sucessfully.\n");
}
/* Fill the local socket address struct */
addr_local.sin_family = AF_INET; // Protocol Family
addr_local.sin_port = htons(PORT); // Port number
addr_local.sin_addr.s_addr = INADDR_ANY; // AutoFill local address
bzero(&(addr_local.sin_zero), 8); // Flush the rest of struct
/* Blind a special Port */
if( bind(sockfd, (struct sockaddr*)&addr_local, sizeof(struct sockaddr)) == -1 )
{
printf ("ERROR: Failed to bind Port %d.\n",PORT);
return (0);
}
else
{
printf("OK: Bind the Port %d sucessfully.\n",PORT);
}
/* Listen remote connect/calling */
if(listen(sockfd,BACKLOG) == -1)
{
printf ("ERROR: Failed to listen Port %d.\n", PORT);
return (0);
}
else
{
printf ("OK: Listening the Port %d sucessfully.\n", PORT);
}
while(1)
{
sin_size = sizeof(struct sockaddr_in);
/* Wait a connection, and obtain a new socket file despriptor for single connection */
if ((nsockfd = accept(sockfd, (struct sockaddr *)&addr_remote, &sin_size)) == -1)
{
printf ("ERROR: Obtain new Socket Despcritor error.\n");
continue;
}
else
{
printf ("OK: Server has got connect from %s.\n", inet_ntoa(addr_remote.sin_addr));
}
/* Child process */
if(!fork())
{
printf("You can enter string, and press 'exit' to end the connect.\n");
while(strcmp(sdbuf,"exit") != 0)
{
scanf("%s", sdbuf);
if((num = send(nsockfd, sdbuf, strlen(sdbuf), 0)) == -1)
{
printf("ERROR: Failed to sent string.\n");
close(nsockfd);
exit(1);
}
printf("OK: Sent %d bytes sucessful, please enter again.\n", num);
}
}
close(nsockfd);
while(waitpid(-1, NULL, WNOHANG) > 0);
}
}
server编译后在PC机上执行,client在板子上运行。
先启动server,再启动client
Usage: ./client HOST_IP (ex: ./client 192.168.0.94)