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Diffstat (limited to 'sync/reader.c')
-rw-r--r--sync/reader.c59
1 files changed, 59 insertions, 0 deletions
diff --git a/sync/reader.c b/sync/reader.c
new file mode 100644
index 0000000..edecf56
--- /dev/null
+++ b/sync/reader.c
@@ -0,0 +1,59 @@
+#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);
+ }
+}