Callback

[wow9999]

Dear all What is Callback? (difinition) when is Callback being used? Thanks

[wb]

example: you want to copy a lot of data.. (10000 GB) this take a long time... and you want to show some kind of progress for the user. so the copy_function have a "callback" parameter, that is a functionpointer to a function, you must suply. the copy_function calls from time to time your "callback" function, so you can show the progress to the user. I hope, this helps.

[David Crow]

wow9999 wrote: What is Callback? (difinition) Per MSDN, it's function that receives messages from the operating system. wow9999 wrote: when is Callback being used? It's used whenever your application needs to be notified of something happening elsewhere. Some examples of functions that utilize callback functions are EnumFontFamilies(), EnumWindows(), qsort(), and RegisterClass().

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