--- sharelite.c~~	2000-04-14 14:24:00 +0400
+++ sharelite.c	2005-10-03 22:35:59 +0400
@@ -22,12 +22,12 @@
 
 /* --- DEFINE MACROS FOR SEMAPHORE OPERATIONS --- */
 
-#define GET_EX_LOCK(A)    semop((A), &ex_lock[0],    3)
-#define GET_EX_LOCK_NB(A) semop((A), &ex_lock_nb[0], 3)
-#define RM_EX_LOCK(A)     semop((A), &ex_unlock[0],  1)
-#define GET_SH_LOCK(A)    semop((A), &sh_lock[0],    2)
-#define GET_SH_LOCK_NB(A) semop((A), &sh_lock_nb[0], 2)
-#define RM_SH_LOCK(A)     semop((A), &sh_unlock[0],  1) 
+#define GET_EX_LOCK(A)    semtimedop((A), &ex_lock[0],    3, &timeout[0])
+#define GET_EX_LOCK_NB(A) semtimedop((A), &ex_lock_nb[0], 3, &timeout[0])
+#define RM_EX_LOCK(A)     semtimedop((A), &ex_unlock[0],  1, &timeout[0])
+#define GET_SH_LOCK(A)    semtimedop((A), &sh_lock[0],    2, &timeout[0])
+#define GET_SH_LOCK_NB(A) semtimedop((A), &sh_lock_nb[0], 2, &timeout[0])
+#define RM_SH_LOCK(A)     semtimedop((A), &sh_unlock[0],  1, &timeout[0])
 
 /* --- DEFINE STRUCTURES FOR MANIPULATING SEMAPHORES --- */
 
@@ -61,6 +61,10 @@
   { 1, -1, (SEM_UNDO | IPC_NOWAIT) } /* remove shared read lock */
 };                                 
 
+static struct timespec timeout[1] = {
+  { 3, 0 } /* 3 sec timeout */
+};
+
 /* USER INITIATED LOCK */
 
 /* returns 0  on success -- requested operation performed   *
@@ -192,10 +196,14 @@
 
 int _detach_segments(Node *node) {
   Node *next_node;
+  struct shmid_ds shmarg;
 
   while(node != NULL) {
     next_node  = node->next;
-    if (shmdt((char *) node->shmaddr) < 0) return -1;
+    if (shmctl(node->shmid,IPC_STAT, &shmarg) < 0) return -1;
+    if (shmarg.shm_nattch > 1) {
+      if (shmdt((char *) node->shmaddr) < 0) return -1;
+    }
     free(node);
     node = next_node;
   }
@@ -205,12 +213,14 @@
 int _remove_segments(int shmid) {
   int    next_shmid;
   Header *shmaddr;
+  struct shmid_ds shmarg;
 
   while(shmid >= 0) {
+    if (shmctl(shmid, IPC_STAT, &shmarg) < 0 && errno == EIDRM) return 0;
     if ((shmaddr = (Header *) shmat(shmid, (char *) 0, 0)) == (Header *) -1) return -1;
     next_shmid = shmaddr->next_shmid;
-    if (shmdt((char *) shmaddr) < 0) return -1;   
     if (shmctl(shmid, IPC_RMID, (struct shmid_ds *) 0) < 0) return -1;
+    if (shmdt((char *) shmaddr) < 0) return -1;   
     shmid = next_shmid;
   }