diff -r 48780e181b38 -r 578be2adaf3e Symbian3/PDK/Source/GUID-AAA2ABA4-5555-5E4B-AEFF-3DF61462B170.dita --- a/Symbian3/PDK/Source/GUID-AAA2ABA4-5555-5E4B-AEFF-3DF61462B170.dita Tue Jul 20 12:00:49 2010 +0100 +++ b/Symbian3/PDK/Source/GUID-AAA2ABA4-5555-5E4B-AEFF-3DF61462B170.dita Fri Aug 13 16:47:46 2010 +0100 @@ -1,31 +1,31 @@ - - - - - -Introduction -to asynchronous programmingThis document introduces the concept of asynchronous programming. -

When a program requests a service, this service can be performed either synchronously or asynchronously.

-

A synchronous service is the normal pattern for function calls where the -function returns and the service requested has either performed successfully -or has failed and an error code returned.

-

An asynchronous service is requested by a function call but completion -occurs later. Completion is indicated by a signal. Between the issue -of the request and the signal, the request is said to be pending. The -requesting program can do other processing while the request is pending or -it can issue a wait. The operating system wakes the program up when -completion of any of its pending requests is signalled.

-

A program may contain a number of independently-executing units, called -threads. All programs have a primary thread, and may create other threads, -possibly for providing or using asynchronous services.

-

If all threads are in a wait state, for example, waiting for user input, -Symbian platform powers down as much as possible of the machine’s electronics. -This results in battery savings and, consequently, a considerable extension -of useful battery life.

+ + + + + +Introduction +to asynchronous programmingThis document introduces the concept of asynchronous programming. +

When a program requests a service, this service can be performed either synchronously or asynchronously.

+

A synchronous service is the normal pattern for function calls where the +function returns and the service requested has either performed successfully +or has failed and an error code returned.

+

An asynchronous service is requested by a function call but completion +occurs later. Completion is indicated by a signal. Between the issue +of the request and the signal, the request is said to be pending. The +requesting program can do other processing while the request is pending or +it can issue a wait. The operating system wakes the program up when +completion of any of its pending requests is signalled.

+

A program may contain a number of independently-executing units, called +threads. All programs have a primary thread, and may create other threads, +possibly for providing or using asynchronous services.

+

If all threads are in a wait state, for example, waiting for user input, +Symbian platform powers down as much as possible of the machine’s electronics. +This results in battery savings and, consequently, a considerable extension +of useful battery life.

\ No newline at end of file