Introduction to the Support Kit

The Support Kit provides a handy set of classes that you can use in your applications. These classes provide:

• Thread Safety. Haiku can execute multiple threads of an application in parallel, letting certain parts of an application continue when one part is stalled, as well as letting an application process multiple pieces of data at the same time on multicore or multiprocessor systems. However, there are times when multiple threads desire to work on the same piece of data at the same time, potentially causing a conflict where variables or pointers are changed by one thread causing another to execute incorrectly. To prevent this, Haiku implements a "locking" mechanism, allowing one thread to "lock out" other threads from executing code that might modify the same data.
• Archiving and IO. These classes allow a programmer to convert objects into a form that can more easily be transferred to other applications or stored to disk, as well as performing basic input and output operations.
• Memory Allocation. This class allows a programmer to hand off some of the duties of memory accounting and management.
• Common Datatypes. To avoid unnecessary duplication of code and to make life easier for programmers, Haiku includes classes that handle management of ordered lists and strings.

There are also a number of utility functions to time actions, play system alert sounds, compare strings, and atomically manipulate integers. Have a look at the overview, or go straight to the complete list of components of this kit.

Overview

• Thread Safety:
  • BLocker provides a semaphore-like locking mechanism allowing for recursive locks.
    • BAutolock provides a simple method of automatically removing a lock when a function ends.
  • Thread Local Storage allows a global variable\'s content to be sensitive to thread context.
• Archiving and IO:
  • BArchivable provides an interface for "archiving" objects so that they may be sent to other applications where an identical copy will be recreated.
    • BArchiver simplifies archiving of BArchivable hierarchies.
    • BUnarchiver simplifies unarchiving hierarchies that have been archived using BArchiver.
  • BFlattenable provides an interface for "flattening" objects so that they may be easily stored to disk.
  • BDataIO provides an interface for generalized read/write streams.
    • BPositionIO extends BDataIO to allow seeking within the data.
      • BBufferIO creates a buffer and attaches it to a BPositionIO stream, allowing for reduced load on the underlying stream.
      • BMemoryIO allows operation on an already-existing buffer.
      • BMallocIO creates and allows operation on a buffer.
• Memory Allocation:
  • BBlockCache allows an application to allocate a "pool" of memory blocks that the application can fetch and dispose of as it pleases, letting the application make only a few large memory allocations, instead of many expensive small allocations.
• Common Datatypes:
  • BList allows simple ordered lists and provides common access, modification, and comparison functions.
  • BString allows strings and provides common access, modification, and comparison functions.
• BStopWatch allows an application to measure the time an action takes.
• Global functions
• Common types and constants
• Error codes for all kits