QtCreator and cURL - final showdown.

[jareq000]

Hi.
I read a hundred sites.
I try to run libraries third day.
But I can't run my code.

I work on Windows 7 64bit
"Tutorial":http://howtofix.pro/tutorial-libcurl-on-qt-creator-with-mingw/
"Qt 5.3.1 for Windows 32-bit (MinGW 4.8.2, OpenGL) ":http://download.qt-project.org/official_releases/qt/5.3/5.3.1/qt-opensource-windows-x86-mingw482_opengl-5.3.1.exe
"Win - MinGW64 7.34.0 devel SSL SSH Günter Knauf":http://curl.haxx.se/gknw.net/7.34.0/dist-w64/curl-7.34.0-devel-mingw64.7z

.pro file:
@TEMPLATE = app
CONFIG += console
CONFIG -= app_bundle

SOURCES += main.cpp

INCLUDEPATH += C:\Qt\Qt5.3.1\5.3\curl-7.34.0-devel-mingw64\include\curl
LIBS += -LC:\Qt\Qt5.3.1\5.3\curl-7.34.0-devel-mingw64\lib64 -lcurl
#LIBS += -LC:\Qt\Qt5.3.1\5.3\curl-7.34.0-devel-mingw64\lib64\libcurldll.a -this also didn't work
@

.cpp file:
@#define CURL_STATICLIB
#include <stdio.h>
#include <curl.h>
#include <easy.h>
#include <string>

size_t write_data(void *ptr, size_t size, size_t nmemb, FILE *stream) {
size_t written;
written = fwrite(ptr, size, nmemb, stream);
return written;
}

int main(void) {
CURL *curl;
FILE *fp;
CURLcode res;
char *url = "http://localhost/aaa.txt";
char outfilename[FILENAME_MAX] = "C:\bbb.txt";
curl = curl_easy_init();
if (curl) {
fp = fopen(outfilename,"wb");
curl_easy_setopt(curl, CURLOPT_URL, url);
curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data);
curl_easy_setopt(curl, CURLOPT_WRITEDATA, fp);
res = curl_easy_perform(curl);
curl_easy_cleanup(curl);
fclose(fp);
}
return 0;
}
@

Always
"error: undefined reference to curl_easy_init'" "error: undefined reference tocurl_easy_setopt'"
"error: undefined reference to `curl_easy_perform'"

I add and link libraries.
I add "#define CURL_STATICLIB"
I copy libcurl dll files to Qt project Release/Debug
but it didn't work.

Please help.

[sierdzio]

Your libraries are binary incompatible: you are trying to link a 64 bit library to a 32 bit program. That will not work. Arhcitectures and compilers must match.

[jareq000]

I tried compile program with MinGW64. Win32 - MSVC also didn't work.
I don't know, why there is no cURL MinGW32.

[sierdzio]

Compile curl yourself, using the compiler from Qt package, then compile your application using the same compiler.

[jareq000]

I find cURL MinGW32 - didn't work. The same fail.
I don't know, how to compile this. It is difficult for me.
I must download Source Archives - curl 7.37.1.zip, yes?
I need to use QtCreator or only MinGW and command line?

[sierdzio]

Then maybe easier option is to download the 64 bit Qt package?

[jareq000]

Yes, but MinGW is only in version Qt 32b. I don't know why.

Erlier I have a problem with version Qt VS, programs didn't compile, so I download MinGW. But some problems still are.

[sierdzio]

I'm so happy to be developing on Linux ;-) Problems like that are pretty much unheard of here.

Maybe there were problems with MinGW64 on Windows, so they have dropped the package, I don't know. You can try compiling Qt yourself, although it's not so easy on Windows.

[jareq000]

So, now:
Qt, MinGW and cURL are for Windows 32-bit, and problem is not solved. Why?
I need to add some packages?
Do I something wrong?

[sierdzio]

They might have been compiled using different version of MinGW. Some versions are not compatible with one another...

or something else is wrong. One thing is certain: the error you are getting is a linker error, so there is no bug on the C++ side.

[jareq000]

Problem solved, but not completly.
All libcurl sources I moved to project folder, and I add:
@INCLUDEPATH += C:...\curl-7.34.0-devel-mingw32\include
LIBS += C:...\curl-7.34.0-devel-mingw32\lib\libcurldll.a
LIBS += C:...\curl-7.34.0-devel-mingw32\lib\libcurl.a
@
But programs exited with code -1073741515, what is the same as 0xC0000135 -> problem with dependency...

The Fight Continues...

[SGaist]

Hi,

You're application is probably not finding the libcurld dll. In Qt Creator go to Project -> run -> PATH and add the path to the folder containing the curl dll

[jareq000]

I added path the libcurl dll (to Projects -> Run -> Run Environment -> Path), but nothing changes.
Still " programs exited with code -1073741515"

[sierdzio]

What happens when you run with the debugger?

[jareq000]

"The gdb process terminated unexpectedely (code 0)"
"Cannot continue debugged process: The program is not being run"
and
"During startup program exited with code 0xc0000135"

Even when I close the terminal window, program is still running (when I want to quit Qt I get a message "Do you want to force quit untitled.exe?)

[jareq000]

I installed Qt Creator 64 bit, Visual Studio 2013, cURL 64bit, and I have
"Cannot obtain a handle to the inferior: The parameter is incorrect."
So I cleaning project, and again
"exited with code -1073741515"

Files are now in release folder
@INCLUDEPATH += C:\Users...\build-one-Qt_64bit-Release\curl-7.34.0-devel-mingw64\include
LIBS += C:\Users...\build-one-Qt_64bit-Release\curl-7.34.0-devel-mingw64\lib64\libcurldll.a
LIBS += C:\Users...\build-one-Qt_64bit-Release\curl-7.34.0-devel-mingw64\lib64\libcurl.a
@

Any suggestions?

Edit:
Qt ask about "curl.lib", so I find it and copy to lib files.
Now Qt want "curldll.lib" and these file I can't find.
Why are they needed? .dll files are not enough?

[jareq000]

Finally, problem solved.
I run untitled.exe form explorer, and message shown, which dll is necessary.
So I download some dll's and it's work.
Thanks for response.