Date: 02-16-2022
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created by gbSnippets
'Background:
'DLLs (*.dll) are used to provide Subs, Functions, or Classes
'which may be called by applications or other DLLs.
'By default, all Subs/Functions/Classes within a DLL are limited
'for use within the DLL, but may also be "Exported" for use by
'applications and other DLLs.
'DLLs make it possible for a programmer to release updates to features
'without having to re-release the entire app, or to provide a single file
'containing common functions that are used by many different applications.
'A DLL can contain any number of Subs/Functions/Classes, some of which
'may be "Exported". A DLL can also contain a main function that is called
'when loading and unloading the DLL.
'In Win32 EXPORTed sub/function names are case-sensitive and by default
'PowerBASIC capitalizes the name of an exported sub/function. Use the
'ALIAS keyword in a Sub/Function statement to provide a preferred,
'non-capitalized name for the EXPORTed sub/function.
'Finally, when a DLL is loaded (and unloaded) Windows runs a specific,
'but optional, function called LibMain. The function is typically used
'to initialize information and to release resources when the application ends.
'It must be declared with four specific arguments, as shown in other snippets
'in this library.
'When the supplied arguments of LibMain are not required, the function
'PBLibMain may be used as a substitute for LibMain. Whichever
'function is used will be called on load and unload of the DLL.
'gbs_00320
'Date: 03-10-2012
http://www.garybeene.com/sw/gbsnippets.htm