39 lines
		
	
	
		
			813 B
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			39 lines
		
	
	
		
			813 B
		
	
	
	
		
			C
		
	
	
	
| #include <stdio.h>
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| #include <stdlib.h>
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| #include <unistd.h>
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| #include <sys/socket.h>
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| #include <netinet/in.h>
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| 
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| int main (int argc, char *argv[])
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| {
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| 	int s, len, o, port = 6666;
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| 	char buf[512];
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| 	struct sockaddr_in addr;
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| 	socklen_t addr_len = sizeof addr;
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| 
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| 	if (argc > 1)
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| 		port = atoi (argv[1]);
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| 
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| 	s = socket (PF_INET, SOCK_DGRAM, IPPROTO_UDP);
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| 
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| 	o = 1;
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| 	len = 4;
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| 	setsockopt (3, SOL_SOCKET, SO_REUSEADDR, &o, len);
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| 
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| 	addr.sin_family = AF_INET;
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| 	addr.sin_port = htons (port);
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| 	addr.sin_addr.s_addr = INADDR_ANY;	/* receive broadcasts */
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| 
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| 	bind (s, (struct sockaddr *) &addr, sizeof addr);
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| 
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| 	for (;;) {
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| 		len = recvfrom (s, buf, sizeof buf, 0, (struct sockaddr *) &addr, &addr_len);
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| 		if (len < 0)
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| 			break;
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| 		if (write (1, buf, len) != len)
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| 			fprintf(stderr, "WARNING: serial characters dropped\n");
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| 	}
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| 
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| 	return 0;
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| }
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