473,396 Members | 2,030 Online
Bytes | Software Development & Data Engineering Community
Post Job

Home Posts Topics Members FAQ

Join Bytes to post your question to a community of 473,396 software developers and data experts.

LockWorkStation Function

How do I lock a Windows 2000 machine in Visual C++.NET 7.1?

#include <windows.h>

bool LockWorkStation()

If I do it fails:

bool LockWorkStation()
{
return true;
}

if doesn't work.

Plus, I'd like to add an IF statement to check if Windows version is Windows
2000 or later then call the LockWorkStation function

Any ideas please?
Mar 5 '07 #1
7 4632
How do I lock a Windows 2000 machine in Visual C++.NET 7.1?
>
#include <windows.h>

bool LockWorkStation()
Why do you declare this function? it is already declared in windows.h
>
If I do it fails:

bool LockWorkStation()
{
return true;
}

if doesn't work.
???? what is the point of implementing your own function that returns true?
what did you think it would do?
>
Plus, I'd like to add an IF statement to check if Windows version is Windows
2000 or later then call the LockWorkStation function
if you use that function in your program, it simply won't run on any OS pre
win2000. The exe will fail with a 'missing entry point' message box or
something like that.

The only way you can do that is by loading user32.dll manually, then using
getprocaddress to find that function, and only call that function if you
found it.

--
Kind regards,
Bruno.
br**********************@hotmail.com
Remove only "_nos_pam"

Mar 6 '07 #2
Bruno

I called the function like so:

using namespace System::Runtime:InteropServices;

[DllImport("user32.dll")]
int LockWorkStation();

Then called it like so:

if (rdoLock)
{
LockWorkStation();
}

Just need to work out the OS version now. In VB.NET I know. Maybe I will
write in VB.NET & convert it

Thanks for you reply, Bruno

--
Newbie Coder
(It's just a name)
Mar 6 '07 #3
using namespace System::Runtime:InteropServices;
>
[DllImport("user32.dll")]
int LockWorkStation();

Then called it like so:

if (rdoLock)
{
LockWorkStation();
}

Just need to work out the OS version now. In VB.NET I know. Maybe I will
write in VB.NET & convert it
I hadn't understood that you are using C#.
For C# questions you' be better off posting to the csharp newsgroup. This is
the C++ newsgroup.

anyway, you could do it the other way around: surround the function call
with a try / catch, and catch the 'EntryPoint not found exception' (don't
know its type).
If you get an exception you can handle the per win2K cases.

--
Kind regards,
Bruno.
br**********************@hotmail.com
Remove only "_nos_pam"

Mar 6 '07 #4

"Bruno van Dooren [MVP VC++]" <br**********************@hotmail.comwrote
in message news:F4**********************************@microsof t.com...
>using namespace System::Runtime:InteropServices;

[DllImport("user32.dll")]
int LockWorkStation();

Then called it like so:

if (rdoLock)
{
LockWorkStation();
}

Just need to work out the OS version now. In VB.NET I know. Maybe I will
write in VB.NET & convert it

I hadn't understood that you are using C#.
For C# questions you' be better off posting to the csharp newsgroup. This
is
the C++ newsgroup.
That is C++, not C# (note the :: scope operator). C++/CLI supports explicit
P/Invoke same as C#, it's not usually as useful as native imports, but
conditional usage is one of the advantages, since it essentially wraps the
LoadLibrary and GetProcAddress calls for you.
>
anyway, you could do it the other way around: surround the function call
with a try / catch, and catch the 'EntryPoint not found exception' (don't
know its type).
If you get an exception you can handle the per win2K cases.

--
Kind regards,
Bruno.
br**********************@hotmail.com
Remove only "_nos_pam"

Mar 6 '07 #5
That is C++, not C# (note the :: scope operator). C++/CLI supports explicit
P/Invoke same as C#, it's not usually as useful as native imports, but
conditional usage is one of the advantages, since it essentially wraps the
LoadLibrary and GetProcAddress calls for you.
I didn't know that C++/CLI supported the DllImport feature.
As soon as I saw that I didn't notice the :: anymore.
Good call. Thanks.

--
Kind regards,
Bruno.
br**********************@hotmail.com
Remove only "_nos_pam"

Mar 7 '07 #6
Yes, it is C++.NET 2003 which I am using

--
Newbie Coder
(It's just a name)
Mar 7 '07 #7

"Bruno van Dooren [MVP VC++]" <br**********************@hotmail.comwrote
in message news:FD**********************************@microsof t.com...
>That is C++, not C# (note the :: scope operator). C++/CLI supports
explicit
P/Invoke same as C#, it's not usually as useful as native imports, but
conditional usage is one of the advantages, since it essentially wraps
the
LoadLibrary and GetProcAddress calls for you.

I didn't know that C++/CLI supported the DllImport feature.
As soon as I saw that I didn't notice the :: anymore.
Good call. Thanks.
It's not dependant on support from the language compiler as far as I know.
Whenever the attribute is placed in the MSIL and seen by the JIT compiler
the runtime will implement P/Invoke regardless of source language.
>
--
Kind regards,
Bruno.
br**********************@hotmail.com
Remove only "_nos_pam"

Mar 7 '07 #8

This thread has been closed and replies have been disabled. Please start a new discussion.

Similar topics

3
by: domeceo | last post by:
can anyone tell me why I cannot pass values in a setTimeout function whenever I use this function it says "menu is undefined" after th alert. function imgOff(menu, num) { if (document.images) {...
5
by: phil_gg04 | last post by:
Dear Javascript Experts, Opera seems to have different ideas about the visibility of Javascript functions than other browsers. For example, if I have this code: if (1==2) { function...
2
by: laredotornado | last post by:
Hello, I am looking for a cross-browser way (Firefox 1+, IE 5.5+) to have my Javascript function execute from the BODY's "onload" method, but if there is already an onload method defined, I would...
2
by: sushil | last post by:
+1 #include<stdio.h> +2 #include <stdlib.h> +3 typedef struct +4 { +5 unsigned int PID; +6 unsigned int CID; +7 } T_ID; +8 +9 typedef unsigned int (*T_HANDLER)(void); +10
8
by: Olov Johansson | last post by:
I just found out that JavaScript 1.5 (I tested this with Firefox 1.0.7 and Konqueror 3.5) has support not only for standard function definitions, function expressions (lambdas) and Function...
3
by: Beta What | last post by:
Hello, I have a question about casting a function pointer. Say I want to make a generic module (say some ADT implementation) that requires a function pointer from the 'actual/other modules'...
2
by: f rom | last post by:
----- Forwarded Message ---- From: Josiah Carlson <jcarlson@uci.edu> To: f rom <etaoinbe@yahoo.com>; wxpython-users@lists.wxwidgets.org Sent: Monday, December 4, 2006 10:03:28 PM Subject: Re: ...
28
by: Larax | last post by:
Best explanation of my question will be an example, look below at this simple function: function SetEventHandler(element) { // some operations on element element.onclick = function(event) {
4
by: alex | last post by:
I am so confused with these three concept,who can explained it?thanks so much? e.g. var f= new Function("x", "y", "return x * y"); function f(x,y){ return x*y } var f=function(x,y){
0
by: Charles Arthur | last post by:
How do i turn on java script on a villaon, callus and itel keypad mobile phone
0
by: emmanuelkatto | last post by:
Hi All, I am Emmanuel katto from Uganda. I want to ask what challenges you've faced while migrating a website to cloud. Please let me know. Thanks! Emmanuel
0
by: Hystou | last post by:
There are some requirements for setting up RAID: 1. The motherboard and BIOS support RAID configuration. 2. The motherboard has 2 or more available SATA protocol SSD/HDD slots (including MSATA, M.2...
0
by: Hystou | last post by:
Most computers default to English, but sometimes we require a different language, especially when relocating. Forgot to request a specific language before your computer shipped? No problem! You can...
0
Oralloy
by: Oralloy | last post by:
Hello folks, I am unable to find appropriate documentation on the type promotion of bit-fields when using the generalised comparison operator "<=>". The problem is that using the GNU compilers,...
0
jinu1996
by: jinu1996 | last post by:
In today's digital age, having a compelling online presence is paramount for businesses aiming to thrive in a competitive landscape. At the heart of this digital strategy lies an intricately woven...
0
by: Hystou | last post by:
Overview: Windows 11 and 10 have less user interface control over operating system update behaviour than previous versions of Windows. In Windows 11 and 10, there is no way to turn off the Windows...
0
tracyyun
by: tracyyun | last post by:
Dear forum friends, With the development of smart home technology, a variety of wireless communication protocols have appeared on the market, such as Zigbee, Z-Wave, Wi-Fi, Bluetooth, etc. Each...
0
agi2029
by: agi2029 | last post by:
Let's talk about the concept of autonomous AI software engineers and no-code agents. These AIs are designed to manage the entire lifecycle of a software development project—planning, coding, testing,...

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.