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#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/shm.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
int main(argc, argv)
int argc;
char **argv;
{
int shmid, i, pid, id;
char *mem, filename[50];
FILE fd;
timeval *s;
if (argc != 1) {
printf("usage: reader [id]\n");
exit(1);
}
id = atoi(argv[1]);
if (argc < 2) {
printf("usage: sync [number readers] [number writers]\n");
exit(1);
}
if ((shmid = shmget(52, 1<<14, IPC_CREAT | 0666)) == -1){
perror("shmget: shmget failed");
exit(1);
}
if ((mem = shmat(shmid, NULL, 0)) == (char *) -1) {
perror("shmat");
exit(1);
}
sprintf(filename, "reader.%d", id);
fd = fopen(filename, "a");
if (!fd) {
perror("fopen: ");
exit(1);
}
srand(time(NULL));
while (1) {
s->tv_sec = rand() % id;
for (i = 0; i < 1<<14; i++) {
fprintf(fd, "%c", *(mem + i));
fflush(fd);
}
select(0, NULL, NULL, NULL, s);
}
}
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