Risistemati ed insiriti nella relativa sezione gli esempi di uso dei

[gapil.git] / sources / message_setter.c

diff --git a/sources/message_setter.c b/sources/message_setter.c
index f6a8408703fd43e7f0cd647cc2ad1a2850c0db87..823f9f8be6a05becb143cfe8b1843b4cf2220631 100644 (file)
--- a/sources/message_setter.c
+++ b/sources/message_setter.c
@@ -92,7 +92,7 @@ int main(int argc, char *argv[])
        printf("Wrong number of arguments %d\n", argc - optind);
         usage();
     }
-    // Get shared memory segment
+    // get shared memory segment
     shm_ptr = FindShm(shmname, MSGMAXSIZE);
     if ( shm_ptr == NULL) {
        perror("Cannot find shared memory");
@@ -103,13 +103,15 @@ int main(int argc, char *argv[])
        perror("Cannot open semaphore");
        exit(1);
     }
+    // get semaphore
     if ( sem_wait(sem) != 0) {
        perror("cannot use semaphore");
        exit(1);
     }
-    strncpy((char *) shm_ptr, argv[optind],  MSGMAXSIZE);
-    printf("Sleeping for %i seconds\n", t); 
-    sleep(t);
+    strncpy((char *) shm_ptr, argv[optind],  MSGMAXSIZE); // modify message
+    printf("Sleeping for %i seconds\n", t);               // print sleep value
+    sleep(t);                                             // sleep
+    // release semaphore
     if ( sem_post(sem) != 0) {
        perror("cannot release semaphore");
        exit(1);