+#ifdef USE_PTHREADS
+/*
+ * Returns a non-null pointer unless a new screen should be allocated because
+ * no match was found in the pre-screen cache.
+ */
+NCURSES_EXPORT(SCREEN *)
+_nc_find_prescr(void)
+{
+ SCREEN *result = 0;
+ PRESCREEN_LIST *p;
+ pthread_t id = GetThreadID();
+ for (p = _nc_prescreen.allocated; p != 0; p = p->next) {
+ if (p->id == id) {
+ result = p->sp;
+ break;
+ }
+ }
+ return result;
+}
+
+/*
+ * Tells ncurses to forget that this thread was associated with the pre-screen
+ * cache. It does not modify the pre-screen cache itself, since that is used
+ * for creating new screens.
+ */
+NCURSES_EXPORT(void)
+_nc_forget_prescr(void)
+{
+ PRESCREEN_LIST *p, *q;
+ pthread_t id = GetThreadID();
+ for (p = _nc_prescreen.allocated, q = 0; p != 0; q = p, p = p->next) {
+ if (p->id == id) {
+ if (q) {
+ q->next = p->next;
+ } else {
+ _nc_prescreen.allocated = p->next;
+ }
+ free(p);
+ break;
+ }
+ }
+}
+#endif /* USE_PTHREADS */
+