diff -urp nvclock0.8b/src/backend/back_linux.c nvclock0.8b-fd/src/backend/back_linux.c
--- nvclock0.8b/src/backend/back_linux.c	2005-08-29 13:44:56.000000000 +0200
+++ nvclock0.8b-fd/src/backend/back_linux.c	2005-10-17 01:03:09.000000000 +0200
@@ -260,6 +260,8 @@ int map_mem(const char *dev_name)
     nv_card.PCIO    = map_dev_mem(fd, nv_card.reg_address + 0x601000, 0x2000);
     nv_card.PRAMDAC = map_dev_mem(fd, nv_card.reg_address + 0x680000, 0x2000);
     nv_card.PROM    = map_dev_mem(fd, nv_card.reg_address + 0x300000, 0xffff);
+
+    close(fd);
     
     return 1;
 }