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In the include file use the extern keyword before usual variable declaration, for instance.
extern int myGlobalInteger;
BTW: use sparingly global variables.
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
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guys just a quick one,how can i access or export the data stored in a varible within my dll, i want to access the data from my msvc++ aplication.
cheers Chris
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In the DLL declare the variable something like
<a name="more">__declspec</a><a name="more">(dllexport) int DLLInt;</a>
In the EXE, something like
<a name="more">__declspec</a><a name="more">(dllimport) int DLLInt;</a>
Since it's easier to declare things in just ONE place, like
a common header file, you can use a macro that imports or exports
the variable depending on what's getting built, the DLL or an EXE...
<a name="more"><font color="Green">
#if defined(BUILDING_DLL)
#define MY_IMP_EXP dllexport
#else
#define MY_IMP_EXP dllimport
#endif
__declspec</a><a name="more">(MY_IMP_EXP) int DLLInt;</a>
Mark
Mark Salsbery
Microsoft MVP - Visual C++
![Java | [Coffee]](https://codeproject.freetls.fastly.net/script/Forums/Images/coffee.gif)
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Your solution is probably much more to the point of what he was interested in than mine  .
Software Zen: delete this;
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Hi there
i'm using GetCursorInfo in order to have the handle to the cursor. How can I know what type of cursor do I have ( ex arrow, hand, wait)???
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duta wrote: How can I know what type of cursor do I have ( ex arrow, hand, wait)???
If it's a custom cursor, then you won't know what it is.
For system predefined cursors, you MAY be able to compare the handle to
the handle returned by LoadCursor() for predefined cursors.
I'm not sure if those handles are always the same but it's easy enough to test
Mark
Mark Salsbery
Microsoft MVP - Visual C++
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Mark Salsbery wrote: ...but it's easy enough to test
Surely you jest!
"Normal is getting dressed in clothes that you buy for work and driving through traffic in a car that you are still paying for, in order to get to the job you need to pay for the clothes and the car and the house you leave vacant all day so you can afford to live in it." - Ellen Goodman
"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne
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No.
And don't call me surely
Mark Salsbery
Microsoft MVP - Visual C++
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A better question is, why do you want to do that? As Mark stated, it's gonna fall apart if someone sets up a custom cursor anyway, and even if that never happens you'd still be depending a good deal on what is essentially an implementation detail of how Windows loads common images... so unless this is a convenience thing (you need to record the current cursor for some reason and want to display a friendly name for it if possible), you're better off finding another way of maintaining state.
---- ...the wind blows over it and it is gone, and its place remembers it no more...
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The Bottom Line is that good programming practice dictates, that you keep track of what you do! That's called Programming!
Bram van Kampen
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Hello,
I have a CDatabase object.In the ExecuteSQL() method I can execute on query but how can I execute more than one SQL queries using the CDatabase object.Or Is there any other class.
Prithaa
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prithaa wrote: how can I execute more than one SQL queries using the CDatabase object
Call ExecuteSQL more than once (?)
Note that if you want to use SQL commands that return records, you need
to use a CRecordset.
Mark
Mark Salsbery
Microsoft MVP - Visual C++
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Hello,
CDatabase C;
C.ExecuteSQL('SELECT SUM(DEMAND) FROM PURCHASE WHERE t='JAN' OR t='FEB' OR t='MAR' INTO FIRSTQUARTER');
In the above SQL FIRSTQUARTER is a variable.
I want to put this variable in another table.
How do I do that?
Here running ExecuteSQL multiple times won't help.
I wanted to run SQL in a batch.
Prithaa
Prithaa.
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prithaa wrote: In the above SQL FIRSTQUARTER is a variable.
So are you wanting something like:
CString str;
str.Format("SELECT SUM(DEMAND) FROM PURCHASE WHERE t='JAN' OR t='FEB' OR t='MAR' INTO %s", FIRSTQUARTER);
C.ExecuteSQL(str);
"Normal is getting dressed in clothes that you buy for work and driving through traffic in a car that you are still paying for, in order to get to the job you need to pay for the clothes and the car and the house you leave vacant all day so you can afford to live in it." - Ellen Goodman
"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne
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Can exceptions in C++ be used without an operating system? How does the compiler implement exceptions with and with out the OS?
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it's up to the compiler's author to implement such choices. BTW, he MUST implement the exceptions system, because as a part of the C++ language, it is something that everyone using this language can excepts to be using.
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If he wants programs to compile for Windows does he have to implement them a certain way?
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No. Windows doesn't force any particular exception mechanism. I would think that processor architecture (call/return and stack implementation, if any) would dictate how exceptions are implemented.
Microsoft built their exception mechanism so that it would co-exist with structured exception handling. SEH was a mechanism built back in the Windows 'C' programming days for critical error handling, which predates compiler-provided exception mechanisms.
Software Zen: delete this;
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Gary R. Wheeler wrote: Windows doesn't force any particular exception mechanism.
How does an exception from a thrown from a native .DLL travel up to an application that uses it? Wouldn't it have to go through Windows?
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CataclysmicQuantums wrote: Wouldn't it have to go through Windows?
No. The C runtime (e.g. MSVCRT) ties the exception system together applying filters and calling installed handlers and the like. Internally it's hooked into signals at the OS level but I don't think it needs them to handle C++ exceptions within a User mode process.
Remember exception handling is all to do with stack manipulation so as long as the excepting functions runtime data is on the same call stack as the handler it doesn't matter which module the code is in.
Nothing is exactly what it seems but everything with seems can be unpicked.
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How do you mean without an operating system. Neither Compiler, nor Computer can work without an Operating System.
The Exception handling mechanism depends on the Compiler and Operating system singing together. Neither will work without the OS. For your own benefit, Just try and investigate 3 points: 1. What's an OS, 2. What do you need to write to make your laptop work whitout Say XP or win95, If all fais Try to run your laptop whitout an Operating System. The best way of trying this is to wipe your hard disk. Do I Get the Point?
I Gave the Long Answer to your question above,
The Short answer is No and NO!
Bram van Kampen
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It’s implementation dependent, as others have alluded to, but on windows it is generally implemented in terms of the OS supplied SEH. All Microsoft compilers (for Windows) layer the compiler’s exception handling code over of OS supplied SEH mechanism. Here’s a link I came across years ago which may be of interest:
A Crash Course on the Depths of Win32™ Structured Exception Handling[^]
Steve
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Thanks that was a good read. I haven't read the entire thing yet but it has already answered some questions I had. Sometimes I get a question stuck in my head and it needs to be answered or else I will obsess.
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