Application Utilities Overview

Application utilities is a collection of libraries that provides low level system and application utility APIs to the platform.

Required background

Before using the libraries of application utilities, you must be familiar with Symbian Resource File syntax, Symbian Descriptors and ECOM plug-ins .


Application utilities is a collection of libraries and has no architectural structure.

The libraries that constitute the Application utilities are:

  • Basic Application Framework Utilities (bafl.dll) - Provides file system utlities, clipboard, command Line Parsing, Descriptor Arrays, Environment Change Notifier, Incremental Matcher, Resource Files, Localised Names of Plug-ins, System Sounds and String Pools.

  • Base Services Utility Library (bsul.dll) - Provides wrapper APIs to validate messages and handle errors. This improves robustness of system servers under IPC attack and ensures secure client server architecture. The library also creates and parses .ini files and provides information about cache drives.

  • Activity Manager (Activitymanger.dll) - Allow clients to monitor for user inactivity (idle time), user activity (key press) and implementing functionalities like screensaver and power management and so on.

  • System Utilities (Sysutil.dll) - Provides system utility API functions to retrieve software and language package version strings for display purposes, check for free space on a disk drive before file creation or writing and retrieve device type information (phone model) for display purposes.