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QuestionUsing WM_USER, WM_APP or RegisterWindowMessage Pin
yccheok9-Dec-10 21:25
yccheok9-Dec-10 21:25 
AnswerRe: Using WM_USER, WM_APP or RegisterWindowMessage [modified] Pin
CPallini9-Dec-10 22:08
mveCPallini9-Dec-10 22:08 
GeneralRe: Using WM_USER, WM_APP or RegisterWindowMessage Pin
Rajesh R Subramanian9-Dec-10 23:43
professionalRajesh R Subramanian9-Dec-10 23:43 
GeneralRe: Using WM_USER, WM_APP or RegisterWindowMessage Pin
CPallini9-Dec-10 23:48
mveCPallini9-Dec-10 23:48 
GeneralRe: Using WM_USER, WM_APP or RegisterWindowMessage Pin
Rajesh R Subramanian9-Dec-10 23:51
professionalRajesh R Subramanian9-Dec-10 23:51 
GeneralRe: Using WM_USER, WM_APP or RegisterWindowMessage Pin
CPallini10-Dec-10 0:11
mveCPallini10-Dec-10 0:11 
GeneralRe: Using WM_USER, WM_APP or RegisterWindowMessage Pin
Rajesh R Subramanian10-Dec-10 0:24
professionalRajesh R Subramanian10-Dec-10 0:24 
GeneralRe: Using WM_USER, WM_APP or RegisterWindowMessage Pin
CPallini10-Dec-10 0:41
mveCPallini10-Dec-10 0:41 
GeneralRe: Using WM_USER, WM_APP or RegisterWindowMessage Pin
Rajesh R Subramanian10-Dec-10 0:54
professionalRajesh R Subramanian10-Dec-10 0:54 
JokeRe: Using WM_USER, WM_APP or RegisterWindowMessage Pin
CPallini10-Dec-10 1:02
mveCPallini10-Dec-10 1:02 
AnswerRe: Using WM_USER, WM_APP or RegisterWindowMessage Pin
Rajesh R Subramanian9-Dec-10 23:42
professionalRajesh R Subramanian9-Dec-10 23:42 
GeneralRe: Using WM_USER, WM_APP or RegisterWindowMessage Pin
CPallini9-Dec-10 23:50
mveCPallini9-Dec-10 23:50 
GeneralRe: Using WM_USER, WM_APP or RegisterWindowMessage Pin
Rajesh R Subramanian9-Dec-10 23:53
professionalRajesh R Subramanian9-Dec-10 23:53 
GeneralRe: Using WM_USER, WM_APP or RegisterWindowMessage Pin
CPallini10-Dec-10 0:21
mveCPallini10-Dec-10 0:21 
GeneralRe: Using WM_USER, WM_APP or RegisterWindowMessage Pin
Rajesh R Subramanian10-Dec-10 0:25
professionalRajesh R Subramanian10-Dec-10 0:25 
GeneralRe: Using WM_USER, WM_APP or RegisterWindowMessage Pin
CPallini10-Dec-10 0:23
mveCPallini10-Dec-10 0:23 
JokeRe: Using WM_USER, WM_APP or RegisterWindowMessage Pin
Rajesh R Subramanian10-Dec-10 0:30
professionalRajesh R Subramanian10-Dec-10 0:30 
AnswerRe: Using WM_USER, WM_APP or RegisterWindowMessage Pin
Gary R. Wheeler11-Dec-10 1:31
Gary R. Wheeler11-Dec-10 1:31 
None of these approaches are inherently more 'secure' than any other.

WM_APP is a little better than WM_USER, because a number of the builtin Windows controls use messages in the WM_USER range.

Both WM_USER and WM_APP messages are easier to detect using Windows Spy++, since they have fixed values.

RegisterWindowsMessage is slightly more difficult to detect, since the value can change each time the message is created (the first time it is called with a given string, a new value is created; further calls with that string get the same value). A determined hack could look for calls to RegisterWindowsMessage and duplicate your string.

One option would be to use a randomly-generated string (such as a GUID) that your application and your DLL's could agree on. A simpler alternative would be to generate a random number between WM_APP and 0xBFFF and pass that to your DLL's via a conventional function call at initialization time.
Software Zen: delete this;
Fold With Us![^]

GeneralRe: Using WM_USER, WM_APP or RegisterWindowMessage Pin
yccheok12-Dec-10 18:51
yccheok12-Dec-10 18:51 
GeneralRe: Using WM_USER, WM_APP or RegisterWindowMessage Pin
Gary R. Wheeler13-Dec-10 11:45
Gary R. Wheeler13-Dec-10 11:45 
QuestionPassing Array To Function & Displaying Array Contents. Pin
Mike Certini9-Dec-10 18:41
Mike Certini9-Dec-10 18:41 
AnswerRe: Passing Array To Function & Displaying Array Contents. Pin
Cedric Moonen9-Dec-10 20:25
Cedric Moonen9-Dec-10 20:25 
GeneralRe: Passing Array To Function & Displaying Array Contents. Pin
Mike Certini10-Dec-10 8:10
Mike Certini10-Dec-10 8:10 
GeneralRe: Passing Array To Function & Displaying Array Contents. Pin
Stefan_Lang14-Dec-10 6:54
Stefan_Lang14-Dec-10 6:54 
AnswerRe: Passing Array To Function & Displaying Array Contents. Pin
Niklas L10-Dec-10 21:13
Niklas L10-Dec-10 21:13 

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