I want to programmatically create a Windows shortcut (.lnk file) to a folder. To do this, I tried this code snippet. However, I get the compilation error C2371 'WebBrowser': redefinition; different basic types in C:\Program Files (x86)\Windows Kits\10\Include\10.0.22000.0\um\exdisp.h line 2367.
Is there a C++17 std::filesystem API for this? If not, how can I fix the compilation error from above? Even with cleaned up includes, the error persists:
#include <Windows.h>
#include <shlguid.h>
#include <shobjidl_core.h>
Using the mklink command yields:
The device does not support symbolic links.
So that doesn't work either, maybe because this is an external SSD.
What else could I try?
The first answer you linked to is the correct way. And it does not rely on WebBrowser at all. It will probably help to define some of the NO_XXX macros before including windows.h.
In my version of ShlGuid.h which is slightly older than yours, I see
#ifndef NO_SHDOCVW_GUIDS
#ifndef GUID_DEFS_ONLY
#include <exdisp.h>
#include <shldisp.h>
#endif
so you can use NO_SHDOCVW_GUIDS to excise the troublesome header that you weren't wanting anyway.
If you wanted support for WebBrowser and the kitchen sink, another fix might be moving #include <windows.h> after ShlGuid.h, as shown e.g. here: https://stackoverflow.com/a/73422757/103167
Links are something that differ a fair amount from filesystem to filesystem, so difficult to standardize. Shell links (.lnk files) are filesystem-independent, but only work on MS Windows (completely non-portable) which also is a strike against finding support in a standard API.
Related
I coded in C++ on Visual Studio (Windows 10) and got this error:
#error The <experimental/filesystem> header providing std::experimental::filesystem is deprecated by Microsoft \
and will be REMOVED. It is superseded by the C++17 <filesystem> header providing std::filesystem. \
You can define _SILENCE_EXPERIMENTAL_FILESYSTEM_DEPRECATION_WARNING to acknowledge that you have received this warning.
With this headers:
#include <iostream>
#include <fstream>
#include <string>
#include <windows.h>
#include <filesystem>//If I will disable it nothing happens.
#include <experimental/filesystem> //If I will disable it happens another error.
namespace fs = std::experimental::filesystem;
using namespace std;
I've tried: #define _SILENCE_EXPERIMENTAL_FILESYSTEM_DEPRECATION_WARNING in the main cpp file. It didnt help.
So then I paste this code from here:
#ifdef __cpp_lib_filesystem
#include <filesystem>
using fs = std::filesystem;
#elif __cpp_lib_experimental_filesystem
#include <experimental/filesystem>
using fs = std::experimental::filesystem;
#else
#error "no filesystem support ='("
#endif
Didn't helped too.
What is the easiest way to get out that error?
Add _SILENCE_EXPERIMENTAL_FILESYSTEM_DEPRECATION_WARNING to Preprocessor definitions.
Project -> Properties -> C/C++ -> Preprocessor -> Preprocessor Definitions.
This solved the issue for me.
According to the link
C++17’s is supported. This is a completely new
implementation, incompatible with the previous std::experimental
version, necessitated by symlink support, bug fixes, and changes in
standard-required behavior. Currently, including provides
the new std::filesystem and the previous
std::experimental::filesystem, and including
provides only the old experimental implementation. The experimental
implementation will be REMOVED in the next ABI-breaking release of the
libraries.
MS abandoned 'experimental' in filesystem.
You could try to use #include <filesystem>instead of #include <experimental/filesystem> and the std::experimental::filesystem is slated for removal, this means you should use std::filesystem.
I had the same problem and then, when I removed the experimental filesystem and added:
#include <filesystem>
namespace fs = std::filesystem;
I would get the error:
namespace “std” has no member “filesystem”
The solution was to go to project properties and do as instructed in the link.
VS2017: E0135 namespace "std" has no member "filesystem"
Adding the define where necessary worked for me:
#define _SILENCE_EXPERIMENTAL_FILESYSTEM_DEPRECATION_WARNING 1;
ie.
#ifdef __cpp_lib_filesystem
#include <filesystem>
namespace fs = std::filesystem;
#elif __cpp_lib_experimental_filesystem
#define _SILENCE_EXPERIMENTAL_FILESYSTEM_DEPRECATION_WARNING 1;
#include <experimental/filesystem>
namespace fs = std::experimental::filesystem;
#else
#error "no filesystem support ='("
#endif
I've been researching this same problem for weeks, and I'm using visual studio 2019 on an Unreal Engine 4 project. It's difficult to enable c++17 headers in visual studio and make them work. A lot of people online suggests using the boost library instead, but this is my attempt in using filesystem because I don't want to deal with trying to download / import external libraries, and so here's what I know...
** Before you start coding in visual studio, you should build / compile your project and see if Visual Studios needs anything set up; for me, I had to download / setup a free license with Incredibuild (there are tutorials online if someone needs to get this setup). Incredibuild is helpful and necessary to build projects in Visual Studio (at least if you're using Unreal Engine 4), but sometimes I get 1 or 2 "errors" in visual studio, but will compile in Unreal Engine 4 because those errors aren't actually errors (people say online that Incredibuild is weird, and wanted to mention that)**
1) How to enable c++17 Headers
When trying to #include which is a c++ version 17 header, it's necessary to enable c++17: Look inside the visual studio "solution explorer" to view the project files, and right-click the project itself and open "properties". Go to the "C/C++ language" tab and switch the version to c++17 (this is easy to find this online). Unless you're doing an Unreal Engine project because there is not a "C/C++ language" tab, so instead find the "NMake" tab and in the text-box to the right of "Addition Options" type in:
/std:c++17 OR /std:c++latest (Microsoft has a list I found online of others, but these are fine)
and visual studios will recognize as a header.
2) How NOT to get c++17 namespaces to work (things I've tried)
After the headers start working you can try to finally make a namespace variable:
namespace fs = std::filesystem; => ERROR: 'std does not have a namespace or class filesystem'
OR if you also #include you can try:
namespace fs = std::experimental::filesystem; OR namespace fs = std::experimental::filesystem::v1; => ERROR: 'we want you to define _SILENCE_EXPERIMENTAL_FILESYSTEM_DEPRECATION_WARNING'
how does one fix these errors?
Online, I found that adding these lines of code to your ProjectName.Build.cs file (which can be found and edited after clicking on the file in "solution explorer") instead of the original declaration for PCHUsage:
PCHUsage = PCHUsageMode.NoSharedPCHs; PrivatePCHHeaderFile = "Folder.h"; CppStandard = CppStandardVersion.Cpp17;
this did get rid of the Errors when using std::filesystem BUT caused wayyyy more problems, and seemed harmful. After looking through other websites / possible solutions, it seems people online don't know how to actually use the filesystem library in visual studio, I've been looking for working code for weeks.
if you want to try and use the std::experimental::filesystem or std::experimental::filesystem::v1, I tried #define _SILENCE_EXPERIMENTAL_FILESYSTEM_DEPRECATION_WARNING, but no dice.
I'm in the same boat as you man, and it looks like you didn't get much help from the previous comments. If we can't find a solution / video tutorial online, I have a plan B. Maybe we could try and write a c++17 project using some different software, or maybe we could write a program using a different software that could be launched instead of enabling c++17 into Visual Studio; for example, if you wanted to list the files in a directory, make an executable file in your preferred other software, and launch that executable / feed it arguments from your visual studio project. That's the best I got man. I hope that sparks some creativity or whatever, but I think it's a lot more helpful than what I've seen online. Good luck to you! and I need that luck too
I have a C++ project in Netbeans on my Linux Mint 17.2 machine. I'm using the GCC 5 toolchain (e.g. g++ 5.3.0), Netbeans 8.1, and Boost 1.61.0.
I'm encountering a weird warning in my project that shows up all over the place. For instance, in my main.cpp, I #include <iostream> at the very top, and that line gets a warning. (I see this warning happen for the first file I include in every file, so it is not an issue with iostream etc.).
The warning is that there is a recursive #include in boost. Specifically, Netbeans complains that <boost/predef/os/bsd/free.h> includes <boost/predef/os/bsd.h> and that <boost/predef/os/bsd.h> includes <boost/predef/os/bsd/free.h>. For the record, this appears to be true - does anyone know why there is this recursive include in boost, and if it is really supposed to be there?
The bigger issue is that my system is not BSD, so I don't know why I'm getting these warnings from the BSD headers, which shouldn't be included or active/defined. I tried printing BOOST_PLATFORM_CONFIG from my main.cpp, and it prints out the path to boost's Linux config header, as expected - not the BSD config header. And, my program compiles and runs fine, so I'm assuming it's never actually using the BSD headers. Which means that the fact that these BSD headers are giving me warnings might be a Netbeans problem, not a boost problem.
Does anyone have any ideas on how to narrow down and fix this issue with these strange recursive include warnings?
I was having the same problem. The issue is with the boost predef/os/bsd.h header. It #includes 5 files in the #else block for the #ifndef BOOST_PREDEF_OS_BSD_H guard. This means that this header file is not guarded against recursion if any of those 5 files also includes bsd.h (which they do).
My solution was to edit the predef/os/bsd.h file and add a recursion guard in the #else block - so, starting at around line 94 my predef/os/bsd.h file now looks like:
#ifndef BOOST_PREDEF_OS_BSD_H_PREVENT_RECURSION <-- ADD THIS
#define BOOST_PREDEF_OS_BSD_H_PREVENT_RECURSION <-- ADD THIS
#include <boost/predef/os/bsd/bsdi.h>
#include <boost/predef/os/bsd/dragonfly.h>
#include <boost/predef/os/bsd/free.h>
#include <boost/predef/os/bsd/open.h>
#include <boost/predef/os/bsd/net.h>
#endif <-- ADD THIS
And now netbeans code assistance is happy and my code still links and compiles without error.
The rough way: comment
#include <boost/predef/os/bsd.h>
Everywhere (should be inside the following headers)
predef/os.h
predef/other/endian.h
Error: cannot open source file "GL/glew.h"
I have the following code :
//Include GLEW
#include <GL/glew.h>
//Include GLFW
#include <GLFW/glfw3.h>
//Include the standard C++ headers
#include <stdio.h>
#include <stdlib.h>
//Define an error callback
static void error_callback(int error, const char* description)
{
...
I took from there: http://www.41post.com/5178/programming/opengl-configuring-glfw-and-glew-in-visual-cplusplus-express#part4
In order to have a somewhat portable solution, before I even started Visual Studio 2013 I created two System Environment Variable in windows.
GLEW=C:\Install\Development\C++\Framework\glew-1.10.0-win32\glew-1.10.0
GLFW=C:\Install\Development\C++\Framework\glfw-3.0.4.bin.WIN32\glfw-3.0.4.bin.WIN32
So in my project I could for instance write a additional include folder as: %GLEW%\include
As I said, it builds fine and runs fine as well.
Yet, not having intellisense behave properly is really annoying.
How to fix it?
My syntax was actually wrong, you cant use global environment variable in VS using %<name>% but you have to use $(%<name>).
Wherever I wrote %GLEW%\include I should have $(GLEW)\include.
It's working fine now.
Though I'm completely clueless why it built.
This post: https://stackoverflow.com/a/11543754/910813 got me to remind that.
I am using opencv with visual studio 2010 windows form application c++. but it wont allow calling inbuilt functions. It gives errors like
Error 1 error C3861: 'cvCvtColor': identifier not found c:\users\ayesha\documents\visual studio 2010\projects\abc\abc\Form1.h 140 1 abc
Error 2 error C3861: 'cvCvtPixToPlane': identifier not found c:\users\ayesha\documents\visual studio 2010\projects\abc\abc\Form1.h 146 1 abc
I have added the following headers
#include "highgui.h"
#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/core/core.hpp"
#include "opencv2/highgui/highgui.hpp"
Can anyone please tell me what i am doing wrong.
Unfortunately, OP doesn't say what version of OpenCV he uses.
While working with OpenCV 3.0, use cvSplit() instead of cvCvtPixToPlane().
cvCvtColor() shall work with OpenCV 3.0, provided you added the required header files to your projects.
Finally, to make sure you don't miss any required files in your project, just start your code with #include <opencv2\opencv.hpp>.
cvCvtColor is a C API function of OpenCV, but you're intending to use the C++ one. You have 2 ways of fixing the problem:
1) (Recommended) Change your source code to use the C++ API. You should use cv::Mat instead of CvArr, cv::cvtColor instead of cvCvtColor, etc.
2) Since such changes in the source code can be pretty involved, you can still use the C API by including C-headers
#include "opencv2/imgproc/imgproc_c.h"
#include "opencv2/core/core_c.h"
#include "opencv2/highgui/highgui_c.h"
instead of the C++ (*.hpp) ones
The error you've mentioned it is a linker error I suppose.
As you're including two headers highgui.hpp and highgui.h targeting to an identical library which is opencv_highgui23#.
Just include only one header.
I am trying to build a C++ app that uses both websocketpp and MySQL. I have encountered 2 build problems using VS 2010 C++ Express.
1) A problem with the boost libraries. It produces many errors like this:
1>c:\program files (x86)\boost\boost_1_50\boost\thread\win32\thread_data.hpp(210): error C2146: syntax error : missing ')' before identifier 'rel_time'
Here's the relevant snippet from thread_data.hpp starting with line 210:
inline BOOST_SYMBOL_VISIBLE void sleep(TimeDuration const& rel_time)
{
interruptible_wait(detail::pin_to_zero(rel_time.total_milliseconds()));
}
2) A conflict with the word VERSION which is documented here and I believe is independent.
To make a clear and simple example of the boost build problems, I'm using the websocketpp example: echo_server.cpp to which I added these includes:
#include "stdafx.h"
Boost lib includes recommended by "Building a program with websocketpp" on the websocketpp site.
#include <boost/regex.hpp>
#include <boost/random.hpp>
#include <boost/system/api_config.hpp>
#include <boost/system/config.hpp>
#include <boost/system/error_code.hpp>
#include <boost/system/system_error.hpp>
#include <boost/system/windows_error.hpp>
and the MySQL header includes. Adding these 2 boostincludes triggers the build errors. If I comment out these 2 includes, it builds without errors:
#include <my_global.h>
#include <mysql.h>
Any suggestions on how to deal with the boost problems?
I don't think this is the same build problem as this one, "Trying to build websocket++ with MinGW: last few linker errors — what could it be?"
Concerning the first error, check if there are any macros interfering with the code. Right-click and go to definition or #define the macro yourself at the beginning of the file and see where it gets redefined. In really hard cases, look at the preprocessor output via a compiler flag.
Concerning the rest, you don't provide any versions for Boost and MySQL. Then, there is my_global.h (or is that part of MySQL?) and stdafx.h, which are both under your control but you don't show them here. Also, try to reduce the issue to the smallest possible piece of code. In short, provide a reproducible example.