--- src/sysdeps/netbsd.c.orig	2008-10-10 07:31:19.000000000 +0200
+++ src/sysdeps/netbsd.c	2008-10-10 07:31:46.000000000 +0200
@@ -505,7 +505,7 @@ gkrellm_sys_battery_read_data(void)
 #endif
   }
 
-   fd = open(SENSORS_DIR, O_RDONLY);
+   fd = open(SENSORS_DIR, O_RDWR);
    if (fd < 0) return;
 
    data.sensor = battery_acpi_data[0].on_line_index;