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Diffstat (limited to 'sync/sync.c')
-rw-r--r--sync/sync.c39
1 files changed, 31 insertions, 8 deletions
diff --git a/sync/sync.c b/sync/sync.c
index 66574a1..23d6ba1 100644
--- a/sync/sync.c
+++ b/sync/sync.c
@@ -1,15 +1,28 @@
#include <stdio.h>
#include <stdlib.h>
#include <sys/ipc.h>
+#include <sys/sem.h>
#include <sys/shm.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
+#define NSEM 3
+
+union semun {
+ int val;
+ struct semid_ds *buf;
+ ushort *array;
+};
+
+
+int shmid, semid;
+
void quit(signum)
int signum;
{
shmctl(shmid, IPC_RMID, NULL);
+ semctl(semid, IPC_RMID, 0);
}
@@ -17,8 +30,9 @@ int main(argc, argv)
int argc;
char **argv;
{
- int shmid, i, pid, n_read, n_write, w;
+ int i, pid, n_read, n_write, w;
char *mem, **arg_r, **arg_w;
+ union semun semarg;
if (argc < 2) {
printf("usage: sync [number readers] [number writers]\n");
@@ -36,13 +50,27 @@ char **argv;
perror("shmat");
exit(1);
}
+printf("Sshmid: %x\n", shmid);
signal(SIGQUIT, quit);
-printf("\nSHMID: %d\nsetting initial memory values...\n", shmid);
for (i = 0; i < 1<<14; i++) {
*(mem + i) = 0x30;
}
+ if ((semid = semget(shmid, NSEM, 0666 | IPC_CREAT)) == -1) {
+ perror("Ssemget: ");
+ exit(1);
+ }
+
+ semarg.val = 1;
+ for (i = 0; i < NSEM; i++) {
+ if ((semctl(semid, i, SETVAL, semarg)) == -1) {
+ perror("semctl: ");
+ exit(1);
+ }
+ }
+
+
arg_r = malloc(sizeof(char*) * 3);
arg_w = malloc(sizeof(char*) * 3);
*arg_r = malloc(sizeof(char) * 10);
@@ -57,11 +85,8 @@ printf("\nSHMID: %d\nsetting initial memory values...\n", shmid);
*(arg_r + 2) = NULL;
*(arg_w + 2) = NULL;
-printf("forking readers...\n");
for (i = 0; i < n_read; i++){
-printf("sprintf...\n");
sprintf(*(arg_r + 1), "%d", i);
-printf("\t%d\n",i);
if (pid = fork()) {
/* printf("starting reader %d...\n", i); */
} else {
@@ -70,10 +95,8 @@ printf("\t%d\n",i);
}
}
-printf("forking writers...\n");
for (i = 0; i < n_write; i++) {
sprintf(*(arg_w + 1), "%d", i);
-printf("\t%d\n", i);
if (pid = fork()) {
/* printf("starting writer %d...\n", i); */
} else {
@@ -89,7 +112,7 @@ printf("sync done...\n");
*/
for (i = 0; i < (n_write + n_read); i++) {
wait(&w);
- printf("\nReturned with code:%d\n", WTERMSIG(w));
+ printf("\nReturned with code:%d\n", WEXITSTATUS(w));
}
quit();
}