I have a need to use CTime in my code. I tried to add the header file "atltime.h" to this code. But now, I am getting so many errors in compiling. Every error is coming from the header file "afxconv.h". I searched msdn for CTime, but they didn't describe about this( may be I yet to see the proper page). I am using VisualStudio-2008, 64 bit. Can anybody point me the correct direction?
Sounds like you are having a conflict with the MFC and ATL version of CTime. Since you specify MFC in your tag I suspect that you want the MFC verion. The atltime.h is for ATL projects. Afx.h has CTime for MFC which AFAIK is normally always included in the stdafx.h
Can you show us your errors?
this code works just fine on a 32 bit computer with a win32 project with atl.
#include "stdafx.h"
#include <atltime.h>
int _tmain(int argc, _TCHAR* argv[])
{
CTime ct;
printf("day of week %d\n",ct.GetDayOfWeek());
return 0;
}
You need to have #include <time.h>. Check the requirements part of the link. MSDN CTime
I included one file from code project, in that it uses some ASSERT,AfxisValidString. They included afx.h, for that. It is also the header for CTime. So, when I removed, and added atltime.h, then the ASSERT related things threw the errors. Sorry, I wated some of your precious time. I am going to vote to delete this question.
Related
Okay. So I've got a simple question. If I ask it in the wrong place, please correct me. What I want to ask is, why Visual Studio gives me this:
#include "stdafx.h"
int main()
{
return 0;
}
everytime I create a new project? (I know I can select Empty Project, and add mine .cpp file by myself, but I'm just curious. It says #include <stdio.h> and #include <tchar.h>. So what is it for? Are you all using it or something?
And P.S - why there is no (int argc, char** argv) in main declaration? (on my coding course in college I've learned that there may be _tmain(int argc, _TCHAR* argv), when creating something in VS)
Okay. So I've got a simple question. If I ask it in the wrong place, please correct me. What I want to ask is, why Visual Studio gives me this:
...
Well, it depends a bit on the project type you've been choosing from the wizard. Looks like the standard template for a console project.
#include "stdafx.h"
is prepended for any type of translation unit by the wizard. It supports the precompiled header optimizaton mechanism.
why there is no (int argc, char** argv) in main declaration?
Because the template provides the minimum for a valid main() entry routine definition.
When creating a new Win32 project, Visual Studio automatically adds a precompiled header "stdafx.h" to your project, even if you unchecked the 'Empty Project' checkbox.
If you want to disable this, go to your project configuration properties -> C/C++ -> Precompiled Headers and select 'Not Using Precompiled Headers'.
Working with precompiled headers see: https://stackoverflow.com/a/4726838.
And P.S. look at -> https://stackoverflow.com/a/4207223
The precompiled header is for speeding up compile times by compiling the contents of your most frequently included headers only once and then reusing the compile results. You can change its name if you want.
I was using Visual C++ 6.0 just now, and I keep getting this error:
fatal error C1083: Cannot open include file: 'streambuf': No such file or directory
My code is just a simple hello world program.
#include "stdafx.h"
#include <iostream>
using namespace std;
int main(int argc, char* argv[])
{
cout<<"Hello World.";
return 1;
}
Then I went and checked my INCLUDE folder and found a file called STREAMBF, but the compiler was looking for STREAMBUF. Notice that the file that is present is missing the U, between the B and the F. This was from a good copy of VC++6.0, directly from the actual CD, not a pirated copy. So there should be all the files needed. But it appears that a file is missing! Is this MS being stupid again, and yet making another big mistake, and forgetting to include an important file on their CDs? I'd hate to think that every single CD for VC++6.0 that was pressed that came out of MS factories had this problem. And I know that it is a missing file, not just a misnamed file, as renaming STREAMBF to STREAMBUF just led to more errors.
Anybody know where I can find a copy of the file STREAMBUF? Or am I just overlooking something here? Is this exact error a known problem with running old copies of VC++ on modern OS's like Windows 7? Is it possible that the only reason that it's looking for STREAMBUF is that this is a newer file associated with Win7, and that if it was running in a different environment (an older OS), it would actually be looking for the correct file, STREAMBF? Can somebody help me here?
Your installation is either broken, deprecated or interpretes your code in wrong way.
You should only use older compiles if you are trying to build project developed entirely for this version.
Try to compile same code with new compiler, if you want to use VS then you should look for Visual Studio Express 2013.
Your code does not have any errors.
Modify your program to, you should be able to see it okay.
#include <iostream.h>
using namespace std;
int main()
{
cout<<"Hello World.";
return 1;
}
However,
your compiler is pretty old. You need to an upgrade.
There are C++ compilers for Windows from Microsoft Express Visual Studios Link and Info VS2013 to
some other non-Microsoft like GCC for Windows.
If you don't have installation access there are some portable c++ compilers.
Finally there are some online compilers for simple test. web based online compilers.
For my win 10 installation of VC 6.0, I had the same problem ... fatal error C1083: Cannot open include file: 'streambuf': No such file or directory
Replacing with <iostream.h> does not solve the problem.
I have checked the header file installation folder (Program files\VS98\VC98\INCLUDE). For some (unknown) reason, some file names have been changed during installation. Restoring the original name has solved the problem, in my case, in example:
Turn STREAMBF into STREAMBUF, STDXCEPT into STDEXCEPT, XCEPTION into EXCEPTION, FCTIONAL into FUNCTIONAL.
Notice: other header file names might be wrong. I have listed above the file names wrong in my installation.
I hope this may help.
I have several global critical sections that need visibility across 3 or more classes defined in 3 or more .cpp files. They're defined in an h file as:
GlobalCS.h
#pragma once
#include "stdafx.h"
extern CRITICAL_SECTION g_cs1;
extern CRITICAL_SECTION g_cs2;
etc...
In a GlobalCS.cpp they are defined
#include "stdafx.h"
#include "GlobalCS.h"
CRITICAL_SECTION g_cs1;
CRITICAL_SECTION g_cs2;
Then in the cpp for the classes they need to work in they're included as
#include "stdafx.h"
#include "GlobalCS.h"
The linker is complaining giving unresolved external in the files where the critical sections are being used. I didn't expect this since the variables are defined as extern. What am I doing wrong or how do I get around this?
error LNK2001: unresolved external symbol "struct _RTL_CRITICAL_SECTION g_CS_SymbolStrPlotAccess" (?g_CS_SymbolStrPlotAccess##3U_RTL_CRITICAL_SECTION##A)
Not sure why you are getting the error. I tried the same thing in Visual Studio and in _tmain function I wrote the following:
int _tmain(int argc, _TCHAR* argv[])
{
//::g_cs1;
ZeroMemory(&g_cs1, sizeof(::g_cs1));
return 0;
}
And it built with no issues whatsoever.
Thank you all for your help. It always is helpful to have sanity checks. The issue was once again Visual Studio setup. Visual Studio will generate link errors if it doesn't like the way you have files added to your project. This is the second bug I've encountered that generated a link error based on the way the project was configured. If it's that important VS should either prevent you from modifying a project in a harmful way or provide a proper error message.
Anyway, the error is the same as this one:
LNK2019 Error under Visual Studio 2010
I had the GlobalCS.h and GlobalCS.cpp in the source directory. I prefer it this way because I find it makes finding files and code faster and in a large c++ project, just moving around the code base is a significant time waster. So much time could be saved writing c++ code if the IDE was designed to help find code faster. 2012 is A LOT better than 2010 so I'll give MSFT that but there could be a lot more features to that end (afterall VS has been around for almost 2 decades now)these types of persistent problems just get in the way of development. When I moved GlobalCS.h to the Header folder and cleaned the project and rebuilt, everything compiled as expected. The other similar error VS will throw at you is when the .h file is in the code directory (so #includes work) but not in the project. I got the same error messages when that happened and it took a good couple days to figure that one out. In a small project, it might not be as problematic but in big solution with multiple projects and dozens of files, it can be problematic.
I have created a file called untitled1.cpp in dev-cpp with the following script:
#include <iostream.h>
using namespace std;
int main(){
cout << "C++";
return 0;
}
But the compiler shows errors like:
1 F:\Dev-Cpp\include\c++\3.4.2\backward\iostream.h:31,
from F:\Dev-Cpp\Untitled1.cpp In file included from
include/c++/3.4.2/backward/iostream.h:31, from
F:\Dev-Cpp\Untitled1.cpp 32:2
F:\Dev-Cpp\include\c++\3.4.2\backward\backward_warning.h #warning This
file includes at least one deprecated or antiquated header. Please
consider using one of the 32 headers found in section 17.4.1.2 of the
C++ standard. Examples include substituting the header for the
header for C++ includes, or instead of the deprecated
header . To disable this warning use -Wno-deprecated.
What is the error that I have? How do I fix it?
In C++ you import the standard library without using the .h suffix.
#include <iostream>
So your fixed example:
#include <iostream>
int main(int argc, char **argv) {
std::cout << "C++";
return 0;
}
Your code is not standard C++. You should say #include <iostream> (no ".h"!). Whatever source you have been learning this from is about 25 years out of date, and you should consider getting some more modern material.
(The "iostreams.h" header was part of a very early non-standard library in the early 1990s, and so it's being kept around for "compatibility" reasons, or to catch very inert programmers and give them a helpful hint.)
Use header file as #include<iostream> instead of #include<iostream.h>
Include iostream instead of iostream.h
This is just a warning.
I think that you could try to include iostream instead of iostream.h in order to fix it.
It says that the header, in this case, iostream.h is deprecated or antiquated. (You only have one header, so that's the one! Just read the error message!)
So you'll have to use iostream, not iostream.h.
You've posted the reason in your question already!
This file includes at least one deprecated or antiquated header.
The real question should therefore be: "Which one is antiquated, how do I replace it?", not "What's the error". Answer: Use <iostream>. The <*.h> versions are pre-standard, legacy headers.
So: Read error messages, people.
I am trying to learn c++ but most of the tutorials and books I have read or looked up teaches you this...
(I am assuming like most tutorials, they are teaching in the beginning to code either in win32 console or CLR console. In either case the following does not work.)
#include <iostream>
int main( )
{
std::cout << "Hello World\n";
return (0);
}
The IDE that i have is Visual C++ 2008 Express edition and they accept code like this
#include "stdafx.h"
int _tmain(int argc, _TCHAR* argv[])
{
return 0;
}
Or like this
#include "stdafx.h"
using namespace System;
int main(array<System::String ^> ^args)
{
Console::WriteLine(L"Hello World");
return 0;
}
Honestly I do not no the difference in none of these and I am not sure if I should just download a older compiler so that it works. If someone can tell me what the difference in these are and where to go from there. That will help tremendously. Thanks
[Edited]
I am trying to do a simple hello world. But I get the error "system can not find path specified." I have screenshot that shows what the error looks like. It also is saying that my project is out of date when I clearly save the file before I build it. Apparently it can not find the executable file. I went to the debug fold and did not see any .exe file.
[Edited]
Ok, now When I try to build the project I get the following errors
1>------ Rebuild All started: Project: test, Configuration: Debug Win32 ------
1>Deleting intermediate and output files for project 'test', configuration 'Debug|Win32'
1>Compiling...
1>stdafx.cpp
1>Compiling...
1>test.cpp
1>c:\users\numerical25\desktop\test\test\test.cpp(1) : warning C4627: '#include <iostream>': skipped when looking for precompiled header use
1> Add directive to 'stdafx.h' or rebuild precompiled header
1>c:\users\numerical25\desktop\test\test\test.cpp(6) : error C2653: 'std' : is not a class or namespace name
1>c:\users\numerical25\desktop\test\test\test.cpp(6) : error C2065: 'cout' : undeclared identifier
1>Build log was saved at "file://c:\Users\numerical25\Desktop\test\test\Debug\BuildLog.htm"
1>test - 2 error(s), 1 warning(s)
========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ==========
Here is the code I used
#include <iostream>
#include "stdafx.h"
int main( )
{
std::cout << "Hello World\n";
return (0);
}
Note: I tried using it with and without the #include "stdafx.h" When I tried it without the #include "stdafx.h", it said I might be missing it.
Not sure what you're asking. The first two examples you gave are valid C++ programs that should (will) compile with VC++. The third example is a C++/CLI program that must be compiled with the /CLR compiler switch (this is called Managed C++).
EDIT: Adding more specific information (from a comment below):
The first two examples are standard (native) C++ (albeit, the second example has MS-proprietary macros). They compile to native code. The third is C++/CLI (a "managed" extension to C++). It compiles to managed (.NET) code. Only the third snippet interacts with the .NET framework in any way. All three are absolutely buildable and runnable using the appropriate projects in VS 2008 (no command line necessary)!
Based on your latest update, it looks like you have probably modified some project properties and changed some paths. The app is building, but when you try to run it via VS (you should do this with <Ctrl>+F5, by the way), the executable cannot be found (there are several ways you could have messed this up by changing or playing with various settings).
Please note the difference between building and running. Building is the process of compiling and linking your source code. Running is launching the resulting executable. You seem to be confused between these (judging from your complaints about the "...out of date" dialog box). It is normal to get the "...out of date" dialog box if you try to run without rebuilding after you have made a change to the project (even if that change is saved). Just make sure you click "yes." You need to build the project before you can run it.
My recommendation is to completely delete your project and solution. Create a new empty project, as suggested elsewhere in this now-very-heavyweight thread, and don't modify any project settings. If this doesn't work, something is seriously wrong!
ANOTHER EDIT: Just for completion, since this question kept changing:
As others have already pointed out, your ultimate problem with the first snippet is the use of precompiled headers (PCH). PCH are turned on by default in new VS C++ projects. Their purpose is to speed compilation when many implementation files include the same set of headers -- preventing the compiler from having to parse the header files for each compilation unit.
You have three options:
(Recommended) Disable PCH -- Project Properties --> Configuration Properties --> C/C++ --> Precompiled Headers: Set Create/Use Precompiled Header to Not Using Precompiled Headers. (You don't need to do anything with the "stdafx.h" file or the #include for it.)
Place your commonly used #includes in "stdafx.h". In your case, you would put #include <iostream> in "stdafx.h".
Place your #includes after `#include "stdafx.h". Microsoft requires that the "stdafx.h" be the first included file in a compilation unit.
A minor point, which I don't see elsewhere in the answers: When using precompiled headers, such as your stdafx.h, you need to include them first. Change it to:
#include "stdafx.h"
#include <iostream>
and that should fix the errors about it.
Alternatively, it may be easier to simply switch off precompiled headers: Project > Properties > Configuration Properties > C/C++ > Precompiled Headers > Switch first option to "Not using precompiled headers". They can be useful for big projects but will just be awkward and annoying while you're learning, since they have extra rules (like this "must be included first") which aren't requirements of standard C++ .
The "difference" is pedantic. The latter are just Microsoft-specific entry points.
As you are learning C++, I recommend you use a compiler, and preferably an operating system that lets you focus on C++, and not the platform. For this I recommend g++, on an Linux distribution such as Ubuntu.
Try this tutorial, there are many others that are similar that quickly let you overcome being tied to the tools, and focus on C++.
int main();
int main(int argc, char* argv[]);
These are standard C++.
int _tmain(int argc, _TCHAR* argv[]);
int wmain(int argc, wchar_t* argv[]);
These are Windows-specific to handle Unicode arguments. See What is the difference between _tmain() and main() in C++?.
int main(array<System::String^>^ args);
This is not C++. This is C++/CLI.
For best portability, always use the first form.
Also,
int main(int argc, char** argv, char** envp);
This is a usually seen POSIX extension. Windows supports this form of main too. The envp means (pointer to) environment variables.
int main(int argc, char** argv, char** envp, char** apple);
This is for Mac only, obviously.
void main();
And this is wrong (nonstandard, some compilers (e.g. gcc) will reject it).
Visual C++ Express will compile the first example just fine.
However, you need to ensure the proper project settings:
Create an "Empty Project"
"Add a new item..." to the project via the "Project" menu. Select C++ (.cpp) file.
Copy/Paste code into new file
Press F5 to compile and run.
When "Project is out of date" dialog appears, press "Yes" (build the project)
The steps above ensure VC++ Express does not treat your file as a special Win32/Windows console application.
EDIT: added additional step 5 to prevent "Can't find..." dialog.
I managed to get the same dialog by making sure the exe file does not exist, and answering "No" to the build dialog. With a clean, empty project the exe file does not exist yet. It must be built first. If you answer "no" don't build it, VC++ dutifully does not build the exe and later complains about not being able to find it when it tries to run it later.
As STingRaySC pointed out, all three of your examples will compile in VC2008 express; it's just that examples 2 and 3 are what VC2008 Express will load up initially when you create a project (one of the examples is for Managed C++, as STingRaySC mentioned).
You can just delete the code in your second example (the C++ Win32 Console Application project) and paste in the more standard hello world program from your first example. It should compile and run just fine in VC2008 Express - it did for me.
I. Precompiled header
#include "stdafx.h"
is some kind of tricky stuff that comes your way.
If you create a project VC will normally switch on precompiled header.
This means that one header stdafx.h is created which is compiled only once.
This is done to speed up compile time in big environments. If you start C++
it will confuse you.
If you use stdafx.h it has to be the first header in the cpp file.
II. Unicode (Utf16)
int _tmain(int argc, _TCHAR* argv[])
Microsoft uses UTF16 to implement unicode strings.
This means you get two versions of main.
int main(int argc, char* argv[])
int main(int argc, wchar_t* argv[])
This is also confusing if you start.
To simply start you can use whatever editor you want.
Create the file.
Open a Visdual studio 2008 command prompt
cl main.cpp
main.exe
and you will see Hello World using code from books.
Afterwards try to understand some of the settings of VC.
But you should always use an empty project.
Else you have to care about stdafx, UNICODE, ...
_tmain with the _TCHAR argv is the way the C runtime allows you to handle unicode. If _UNICODE is defined, then _tmain will expand to wmain, and the _TCHAR argument will be of type wchar_t. If _UNICODE is not defined, then _tmain will expand to main, which will be the ANSI standard.
Therefore, so long as _UNICODE is not defined, the second snippet you posted is compliant with the standard.
Lots of waxing lyrical and some misinformation for you sift through already, but I suggest following wonsungi's advice. But to clarify his advice:
File->New->Project
Select Project Type "Win32", then Template "Win32 Console Project"
Give the project a name and location
OK
Select "Application Settings"
Check "Empty Project"
In the "Solution Explorer", right click the "Sources" folder, then Add->New Item
Type the name of the file, in the "name" box using a .cpp extension (you can ignore the templates if you wish).
Enter your code in the new file.
Woot!! I figured it out!!! Below is my original code
#include <iostream>
int main( )
{
std::cout << "Hello World\n";
return (0);
}
It was missing the header file #include "stdafx.h" . So I had to include it in there so I added it like this
#include <iostream>
#include "stdafx.h"
int main( )
{
std::cout << "Hello World\n";
return (0);
}
I was still getting an error like what you see in my edited question at the bottom. So What I did is I took #include and added it in my header file and then it worked!!!!!
Even the the books and alot of tutorials show to add #include to the actual cpp, for some reason in express edition I had to add it to header for it to work. I don't know WHY but it's a solution and now it works.
Download and install Dev-C++ on your system. If the code doesn't work on Visual C++, try it out on Dev-C++ (which uses the GCC compiler). You may get the same results or a different error message. Whenever you get an error message you don't understand, do a Internet search for the error message.