我有一个程序应该同时读取串行端口和 tcp/ip 套接字。
但是，当我通过套接字接收消息时，我只能看到串行信息。我相信这与 accept() 方法的阻塞/非阻塞有关。但是，我一直未能弄清楚如何为其添加标志。
有人有想法么？
我必须重写整个事情还是可以只添加一个标志？
int main(int argc, char *argv[]) {
int list_s; /* listening socket */
int conn_s; /* connection socket */
short int port; /* port number */
struct sockaddr_in servaddr; /* socket address structure */
char buffer[MAX_LINE]; /* character buffer */
char *endptr; /* for strtol() */
/* Get port number from the command line, and
* set to default port if no arguments were supplied */
if ( argc == 2 ) {
port = strtol(argv[1], &endptr, 0);
if ( *endptr ) {
fprintf(stderr, "ECHOSERV: Invalid port number.\n");
exit(EXIT_FAILURE);
}
}
else if ( argc < 2 ) {
port = ECHO_PORT;
}
else {
fprintf(stderr, "ECHOSERV: Invalid arguments.\n");
exit(EXIT_FAILURE);
}
/* Create the listening socket */
if ( (list_s = socket(AF_INET, SOCK_STREAM, 0)) < 0 ) {
fprintf(stderr, "ECHOSERV: Error creating listening socket.\n");
exit(EXIT_FAILURE);
}
/* Set all bytes in socket address structure to
* zero, and fill in the relevant data members */
memset(&servaddr, 0, sizeof(servaddr));
servaddr.sin_family = AF_INET;
servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
servaddr.sin_port = htons(port);
/* Bind our socket addresss to the
* listening socket, and call listen() */
if ( bind(list_s, (struct sockaddr *) &servaddr, sizeof(servaddr)) < 0 ) {
fprintf(stderr, "ECHOSERV: Error calling bind()\n");
exit(EXIT_FAILURE);
}
if ( listen(list_s, LISTENQ) < 0 ) {
fprintf(stderr, "ECHOSERV: Error calling listen()\n");
exit(EXIT_FAILURE);
}
/* Enter an infinite loop to respond
* to client requests and echo input */
int result = 0;
int portID = -1;
char *device = "/dev/ttyUSB1";
int rate = convertRate("115200");
char parity = convertParity("N");
int databits = convertDatabits("8");
int stopbits = convertStopbits("1");
portID = posixComOpen(device,rate,parity,databits,stopbits);
while ( 1 ) {
char input = 0;
while(posixComDataReady(portID) && posixComRead(portID, &input)) {
printf("%c", input);
} //while
/* Write character to Vex */
if(posixComWrite(portID, 'x') < 0)
printf("POSIX: Error Writing char %c",'x');
/* Wait for a connection, then accept() it */
if ( (conn_s = accept(list_s, NULL, NULL) ) < 0 ) {
fprintf(stderr, "ECHOSERV: Error calling accept()\n");
exit(EXIT_FAILURE);
}
/* Retrieve an input line from the connected socket
* then simply write it back to the same socket. */
Readline(conn_s, buffer, MAX_LINE-1);
printf("Netbook got a TCP/IP message: %s\n", buffer);
char* sendMessage = "Thanks for the message!";
Writeline(conn_s,sendMessage , strlen(sendMessage));
/* Close the connected socket */
if ( close(conn_s) < 0 ) {
fprintf(stderr, "ECHOSERV: Error calling close()\n");
exit(EXIT_FAILURE);
}
}//while
return 0;
}