C / C++ / MFC Discussion Boards

Re: same structure behave differntly in different application

Zac Howland12-Jul-06 3:41

Zac Howland

12-Jul-06 3:41

pavan105nagarbhavi wrote:
struct lat_lon1 {
char news;
short deg;
short min;
float sec;
}lat;

With the default compiler switches/directives, this structure will be packed as follows:

struct lat_lon1 
{
	char news;	// 1 byte
	char junk1;	// 1 byte
	short deg;	// 2 bytes and must be on 2-byte boundary
	short min;	// 2 bytes and must be on 2-byte boundary
	short junk2;	// 2 bytes and must be on a 2-byte boundary
	float sec;	// 4 bytes and must be on a 4-byte boundary
}lat;

That is where you get the sizeof(lat_lon1) == 12 from. Now, with some varying directives (#pragma pack for example), you could get it packed as follows:

struct lat_lon1 
{
	float sec;	// 4 bytes and must be on a 4-byte boundary
	char news;	// 1 byte
	char junk1;	// 1 byte
	short deg;	// 2 bytes and must be on 2-byte boundary
	short min;	// 2 bytes and must be on 2-byte boundary
}lat;

which would give you sizeof(lat_lon1) == 10. This is a very good example of why it is important to declare variables in a certain order for complex types.

If you decide to become a software engineer, you are signing up to have a 1/2" piece of silicon tell you exactly how stupid you really are for 8 hours a day, 5 days a week

Zac

Registry - RegSetValuEx - Returning Access denied ??

elitecodex12-Jul-06 1:43

elitecodex

12-Jul-06 1:43

Hey everyone. I have a function that reads in a registry value (for
the windows firewall) and one that disables it.

<code>
void wxJobsPanel::DisableWindowsFirewall()
{
HKEY hkeyFirewall;

/*
if ( RegOpenKeyEx(HKEY_LOCAL_MACHINE, registryLocations[0], 0, KEY_ALL_ACCESS, &hkeyFirewall) != ERROR_SUCCESS)
wxLogError("FAILED - Could not open the firewall policy registry entry");
*/
if ( RegCreateKeyEx(
HKEY_LOCAL_MACHINE,
registryLocations[0],
0,
NULL,
REG_OPTION_NON_VOLATILE,
KEY_WRITE,
NULL,
&hkeyFirewall,
NULL) != ERROR_SUCCESS )
wxLogError("FAILED - Could not open the firewall policy registry entry");

else
{
DWORD value = 0;
if ( RegSetValueEx(hkeyFirewall, "EnableFirewall", 0, REG_DWORD, (LPBYTE) &value, sizeof(DWORD)) != ERROR_SUCCESS )
{
ErrorString("DisableWindowsFirewall()");
wxLogError("FAILED - Could not set the EnableFirewall value");
}
RegCloseKey(hkeyFirewall);
}
}</code>

The error is in RegSetValue. It returns "Access denied". ErrorString
is almost taken completely out of the PlatformSDK which is how Im
getting the error. Ive tried both methods above, using both the RegCreateKeyEx and RegOpenKeyEx. I can open (and read in a different function) with no problem. I can edit the value no problem using regedit. Just this seems to fail and I do not know why.

I've also tried opening the key with KEY_ALL_ACCESS and KEY_SET_VALUE
in combination with KEY_WRITE | KEY_READ.

Any ideas? The user is in the Administrator group. Thanks!

Re: Registry - RegSetValuEx - Returning Access denied ??

Steve S12-Jul-06 3:11

Steve S

12-Jul-06 3:11

Why fiddle with the registry at all? Why not just use the INetFwRemoteAdminSettings interface to the firewall in the first place?

[fx:mutters]
honestly, what's the point in having a published API if people are just going to hack the registry anyway....
[fx:off]

Steve S
Developer for hire

Re: Registry - RegSetValuEx - Returning Access denied ?? [modified]

elitecodex12-Jul-06 4:51

elitecodex

12-Jul-06 4:51

I would have loved to avoid the registry hacking if I could... and I thank you for pointing that out. However, all the examples in the PlatformSDK for the Windows Firewall API are in VB... which doesn't help. Also, Im not the biggest fan of COM and that looks to be what I have to go through... I would rather just have something like the IP Helper API... makes my life easier
Any other suggestions?

Ok, I found this link...

http://msdn.microsoft.com/library/en-us/ics/ics/exercising_the_firewall.asp[^]

And basically followed that to get it working... and it worked like a charm. I wish they would have put the C++ examples in the PSDK but eh... I found it.

Thanks for the direction Steve!

-- modified at 11:32 Wednesday 12th July, 2006

Re: Registry - RegSetValuEx - Returning Access denied ??

Steve S12-Jul-06 6:51

Steve S

12-Jul-06 6:51

No problem. I agree with most of your original comment (although I am a fan of COM, DCOM (which is COM with hiking boots on) and COM+, which is something else).

Luckily (?) I can generally read VB and mentally convert to roughly equivalent VC++ code, although it does get messy sometimes. I couldn't remember/find the link myself, or I'd have posted it, but it's that same stuff I read.

The pain for me is that I find myself working on customer sites where they have VC6 and so the platform SDK is fixed at Feb 2003 (or sometimes earlier!), so I often find myself writing wrapper classes to expose stuff like the firewall functionality without needing to include the later PSDK headers or link in the later PSDK import libraries; as for UUID.LIB, just don't ask, all right? Thank BG for __declspec(uuid), that's all I say!

If you hadn't got the link, I'd have snipped a section of source from one of the utilities I wrote which enables the firewall, opens some ports up (for DCOM use) and configures DCOM to use those ports. I'm ashamed to admit it, but that last part does hack the registry, as I haven't found the API to do it 'officially'... Cry | :((

Steve S
Developer for hire

Problem with size of child window

g_sandipan12-Jul-06 1:16

g_sandipan

12-Jul-06 1:16

I am working with a MDI window, where my child window (viwe) is derived from CFromView. With my windows setting the size of form template is (x = 336, y = 218) (as seen from resource view). But when i am loading the child window it gets some default size, which i am not able trace out. My question is how to stop this defaulting setting and assign the actual size (which is the size the from template) ? Please help me to get the solution.

Sandip

Re: Problem with size of child window [modified]

Sarath C12-Jul-06 1:29

Sarath C

12-Jul-06 1:29

Resize it in OnInitialUpdate function
code snippet added:

CFormView::OnInitialUpdate();
GetParentFrame()->MoveWindow(100,100,200,200);
ResizeParentToFit();

SaRath.

"Where I am from, there is no plan B. So, take advantage of today becuase tomorrow is not promised. - 50 Cent"

My Blog | Understanding State Patte

-- modified at 7:38 Wednesday 12th July, 2006

Re: Problem with size of child window

g_sandipan12-Jul-06 2:00

g_sandipan

12-Jul-06 2:00

Thanks for the suggestion and the code snippet.
Its working fine.

But how do i get the size of from template, which is associated with my view class?

Best Regards

Sandip

pressing return in an edit control

Desmo1612-Jul-06 0:38

Desmo16

12-Jul-06 0:38

Hi all,

When i run my MFC application,
if i click in an edit control an
press the "return" button the application
exits.

Why ?
How can i avoid that ?

Thanx in advance,
Desmo16.

Re: pressing return in an edit control

Sarath C12-Jul-06 0:45

Sarath C

12-Jul-06 0:45

Set edit box style from resource editor as "Want return"
or pEdit->ModifyStyle(0,ES_WANTRETURN);

SaRath.

"Where I am from, there is no plan B. So, take advantage of today becuase tomorrow is not promised. - 50 Cent"

My Blog | Understanding State Patte

Re: pressing return in an edit control [modified]

see me12-Jul-06 1:13

see me

12-Jul-06 1:13

I think this will not work..

try this....
simply overide the OnOK() and do not call CDialog::OnOK()

OnOK(){}

Else give Multiline property to edit box

Dream bigger... Do bigger...Expect smaller
aji

-- modified at 7:14 Wednesday 12th July, 2006

Re: pressing return in an edit control

Hamid_RT12-Jul-06 1:16

Hamid_RT

12-Jul-06 1:16

and OnCancel for Esc

whitesky

Re: pressing return in an edit control

Sarath C12-Jul-06 1:27

Sarath C

12-Jul-06 1:27

You can also aproach PretranslateMessage function

SaRath.

"Where I am from, there is no plan B. So, take advantage of today becuase tomorrow is not promised. - 50 Cent"

My Blog | Understanding State Patte

Re: pressing return in an edit control

FarPointer12-Jul-06 1:49

FarPointer

12-Jul-06 1:49

PretranslateMessage
OMG | :OMG:

Regards,
FarPointer
Blog:FARPOINTER

Re: pressing return in an edit control

Naveen12-Jul-06 0:47

Naveen

12-Jul-06 0:47

set the Want Return style for the edit control.

if u dont want to ur application when the enter key is pressed,

simply overide the OnOK() funtion in the dialog class. Inside that funtion do not call CDialog::OnOK()..

nave

Re: pressing return in an edit control

Naveen12-Jul-06 1:11

Naveen

12-Jul-06 1:11

forgot to say set the multiline property(ES_MULTILINE) also to the edit box.

nave

Re: pressing return in an edit control

ThatsAlok12-Jul-06 0:57

ThatsAlok

12-Jul-06 0:57

Desmo16 wrote:

Hi all,

When i run my MFC application,
if i click in an edit control an
press the "return" button the application

Also make you Edit Control Multiline!

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

cheers,
Alok Gupta
VC Forum Q&A :- I/ IV
Support CRY- Child Relief and You

Re: pressing return in an edit control

Hamid_RT12-Jul-06 1:02

Hamid_RT

12-Jul-06 1:02

You can set Want return to true in property window from editbox

whitesky

Shell Execute

anu_8812-Jul-06 0:06

anu_88

12-Jul-06 0:06

Hai
can any one pls tell what is ShellExecute command ? and when do we use it?

Thanks in advance Smile | :)

Re: Shell Execute

Jonathan [Darka]12-Jul-06 0:09

Jonathan [Darka]

12-Jul-06 0:09

Don't be so lazy - look it up yourself.

Here is a hint....

http://www.google.com/search?hl=en&lr=&q=shellexecute&btnG=Search

or try MSDN - that is what it is for.

regards,

Darka [Xanya]

Re: Shell Execute

Ganesh_T12-Jul-06 0:50

Ganesh_T

12-Jul-06 0:50

Try to use msdn...always....

This function is used to start the external exe... from you application .

"A winner is not one who never fails...but the one who never quits"

Re: Shell Execute

David Crow12-Jul-06 3:05

David Crow

12-Jul-06 3:05

Ganesh_T wrote:
This function is used to start the external exe...

Actually, it all depends on the verb. The "open" verb is one of many that are used by ShellExecute().

"The largest fire starts but with the smallest spark." - David Crow

"Judge not by the eye but by the heart." - Native American Proverb

Re: Shell Execute

ThatsAlok12-Jul-06 0:57

ThatsAlok

12-Jul-06 0:57

manognya wrote:
an any one pls tell what is ShellExecute command ? and when do we use it?

http://www.codeproject.com/system/newbiespawn.asp[^]

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

cheers,
Alok Gupta
VC Forum Q&A :- I/ IV
Support CRY- Child Relief and You

Re: Shell Execute

Jonathan [Darka]12-Jul-06 1:06

Jonathan [Darka]

12-Jul-06 1:06

Good response - I couldn't remember where that article was.
Smile | :)

Darka [Xanya]

Re: Shell Execute

ThatsAlok12-Jul-06 1:45

ThatsAlok

12-Jul-06 1:45

Darka wrote:
Good response - I couldn't remember where that article was.

You are Welcome Smile | :)

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

cheers,
Alok Gupta
VC Forum Q&A :- I/ IV
Support CRY- Child Relief and You

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