50 lines
1.1 KiB
C
50 lines
1.1 KiB
C
#include <arpa/inet.h>
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#include <netinet/in.h>
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#include <stdio.h>
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <unistd.h>
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#include <sys/time.h>
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#include <stdlib.h>
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#include <string.h>
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#define BUFLEN sizeof(struct timeval)
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#define PORT 9876
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void diep(char * s)
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{
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perror(s);
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exit(1);
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}
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int main(void)
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{
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struct sockaddr_in si_me, si_other;
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int s, slen = sizeof(si_other);
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struct timeval buf;
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if ((s = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1)
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diep("socket");
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memset((char *) &si_me, 0, sizeof(si_me));
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si_me.sin_family = AF_INET;
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si_me.sin_port = htons(PORT);
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si_me.sin_addr.s_addr = htonl(INADDR_ANY);
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if (bind(s, (struct sockaddr *) &si_me, sizeof(si_me)) == -1)
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diep("bind");
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for (;;)
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{
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if (recvfrom(s, &buf, BUFLEN, 0,
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(struct sockaddr *) &si_other, &slen) == -1)
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diep("recvfrom()");
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if (sendto(s, &buf, BUFLEN, 0,
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(struct sockaddr *) &si_other, slen) == -1)
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diep("sendto()");
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}
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close(s);
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return 0;
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}
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