Sending a HTML form using a C++ console application?

[SineCosine]

Umm..
I've been googling for days now, (Maybe even months, never kept track) and haven't found an answer to my question.

You know those HTML forms that you submit with the click of a button after filling in a variety of text-fields?

How would one send those HTML forms using C++?
As in, no need to open a browser.

Googling only ever got me vague explanations of what sockets are and that I'd be needing them.
But nothing put in layman terms =x

If anyone could spare some time to tell me what libraries I'd need along with some guidance.. I'd be grateful

 

[celerisk]

You could start with the reply given here:
http://www.thehelper.net/forums/showthread.php?t=151130

 

[SineCosine]

I just got back home =)
Umm..
Forgive me if this sounds stupid, but..

#include <fstream>
 
#include <cstdlib>
#include <cerrno>
 
#include <curlpp/curlpp.hpp>
#include <curlpp/Easy.hpp>
#include <curlpp/Options.hpp>
#include <curlpp/Exception.hpp>
 
int main(int argc, char *argv[])
{
  if(argc < 2) {
    std::cerr << argv[0] << ": Wrong number of arguments" << std::endl 
        << "Usage: " << argv[0] << " url"
        << std::endl;
    return EXIT_FAILURE;
  }
 
  char *url = argv[1];
 
  try {
    curlpp::Cleanup cleaner;
    curlpp::Easy request;
 
    request.setOpt(new curlpp::options::Url(url)); 
    //request.setOpt(new curlpp::options::Verbose(true)); 
 
    {
      // Forms takes ownership of pointers!
      curlpp::Forms formParts;
      formParts.push_back(new curlpp::FormParts::Content("name1", "value1"));
      formParts.push_back(new curlpp::FormParts::Content("name2", "value2"));
 
      request.setOpt(new curlpp::options::HttpPost(formParts)); 
    }
 
    // The forms have been cloned and are valid for the request, even
    // if the original forms are out of scope.
    std::ofstream myfile("/dev/null");
    myfile << request << std::endl << request << std::endl;
  }
  catch ( curlpp::LogicError & e ) {
    std::cout << e.what() << std::endl;
  }
  catch ( curlpp::RuntimeError & e ) {
    std::cout << e.what() << std::endl;
  }
 
  return EXIT_SUCCESS;
}

This part:
int main(int argc, char *argv[])
Umm..
How are you allowed to pass arguments to the main function?
Isn't it, like, the first function that's run when you run an application?
How do you pass arguments to a function that is run immediately?

[EDIT]
Ugh, I can't do it.
I can't seem to compile/build libcurl using Microsoft Visual C++ 2008 Express.

So.. many.. errors..
So.. many.. different googled tutorials..
Nothing for Microsoft Visual C++ 2008 Express =/

[EDIT=2]

1>------ Build started: Project: libcurl, Configuration: Debug Win32 ------
1>Compiling...
1>stdafx.cpp
1>libcurl.cpp
1>Generating Code...
1>Linking...
1>libcurl.obj : error LNK2019: unresolved external symbol __imp__curl_easy_cleanup referenced in function _main
1>libcurl.obj : error LNK2019: unresolved external symbol __imp__curl_easy_perform referenced in function _main
1>libcurl.obj : error LNK2019: unresolved external symbol __imp__curl_easy_setopt referenced in function _main
1>libcurl.obj : error LNK2019: unresolved external symbol __imp__curl_easy_init referenced in function _main
1>C:\MyFirstAttempt\libcurl\Debug\libcurl.exe : fatal error LNK1120: 4 unresolved externals
1>Build log was saved at "file://c:\MyFirstAttempt\libcurl\libcurl\Debug\BuildLog.htm"
1>libcurl - 5 error(s), 0 warning(s)
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

Build Log      Build started: Project: libcurl, Configuration: Debug|Win32
 Command Lines      Creating temporary file "c:\MyFirstAttempt\libcurl\libcurl\Debug\RSP00002F10121884.rsp" with contents
[
/Od /I "C:\MyFirstAttempt\libcurl\include" /D "WIN32" /D "_DEBUG" /D "_CONSOLE" /D "_UNICODE" /D "UNICODE" /Gm /EHsc /RTC1 /MDd /Fo"Debug\\" /Fd"Debug\vc90.pdb" /W3 /c /ZI /TP .\libcurl.cpp

.\stdafx.cpp
]
Creating command line "cl.exe @c:\MyFirstAttempt\libcurl\libcurl\Debug\RSP00002F10121884.rsp /nologo /errorReport:prompt"
Creating temporary file "c:\MyFirstAttempt\libcurl\libcurl\Debug\RSP00003010121884.rsp" with contents
[
/OUT:"C:\MyFirstAttempt\libcurl\Debug\libcurl.exe" /INCREMENTAL /LIBPATH:"C:\MyFirstAttempt\libcurl" /MANIFEST /MANIFESTFILE:"Debug\libcurl.exe.intermediate.manifest" /MANIFESTUAC:"level='asInvoker' uiAccess='false'" /DEBUG /PDB:"C:\MyFirstAttempt\libcurl\Debug\libcurl.pdb" /SUBSYSTEM:CONSOLE /DYNAMICBASE /NXCOMPAT /MACHINE:X86 C:\MyFirstAttempt\libcurl\lib\libcurl.lib kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib

".\Debug\stdafx.obj"

".\Debug\libcurl.obj"

".\Debug\libcurl.exe.embed.manifest.res"
]
Creating command line "link.exe @c:\MyFirstAttempt\libcurl\libcurl\Debug\RSP00003010121884.rsp /NOLOGO /ERRORREPORT:PROMPT"
 Output Window      Compiling...
stdafx.cpp
libcurl.cpp
Generating Code...
Linking...
libcurl.obj : error LNK2019: unresolved external symbol __imp__curl_easy_cleanup referenced in function _main
libcurl.obj : error LNK2019: unresolved external symbol __imp__curl_easy_perform referenced in function _main
libcurl.obj : error LNK2019: unresolved external symbol __imp__curl_easy_setopt referenced in function _main
libcurl.obj : error LNK2019: unresolved external symbol __imp__curl_easy_init referenced in function _main
C:\MyFirstAttempt\libcurl\Debug\libcurl.exe : fatal error LNK1120: 4 unresolved externals
 Results      Build log was saved at "file://c:\MyFirstAttempt\libcurl\libcurl\Debug\BuildLog.htm"
libcurl - 5 error(s), 0 warning(s)

[EDIT=3]
That came across wrongly, I can build it, I do have the .lib and .dll files along with the include folder from building it.
But I can't figure out how to make VC++ 2008 include those files in a project so that I can use the functions =/

The more I google, the bigger my headache gets >.<

 

[celerisk]

" unresolved external symbol "

You didn't tell the linker to include the library.
Project > Configuration / Settings / Properties (or something similar) > Linker > Command line?
(Or something vaguely looking like it. Ages since I last used VC)



" ... using a C++ console application "

Ehm... you're building a console application and never used the console?
Well, open a "command prompt".
Use "cd" (with tab if you are too lazy to type) to navigate to the folder your program is in.
Type the name and add whatever parameters you want.

Something like this:
C:\> cd /users/celerisk/My Documents/Development/my project/
program-name parameter1 parameter2 ...

Or create a shortcut to it, edit its properties and add them after the "target".

 

[SineCosine]

I could have sworn I did tell it to include it.. *Scratches head*
I've only ever learned to play around with:

cin, cout, getline, stringstream, variables, etc. xD
I don't know any of the.. Erm..
C++ natives (I think you call them that, like, opening a file, creating one, read from one, forcing a global key press, detecting a keypress, etc.)

I did it for the include and library paths..
Is there anything else I'd need to add? o.0

[EDIT]
This is what I entered for: Additional Include Directories

"C:\MyFirstAttempt\curl-7.21.0\include\curl";"C:\MyFirstAttempt\curl-7.21.0\include"

This is what I entered for: Additional Library Directories

"C:\MyFirstAttempt\curl-7.21.0\lib\DLL-Debug";"C:\MyFirstAttempt\curl-7.21.0\lib\LIB-Debug";"C:\MyFirstAttempt\curl-7.21.0\lib"

[EDIT=2]
Wait-
You were right:
Project > Configuration / Settings / Properties (or something similar) > Linker > Command line
I didn't add libcurl.lib =x

But after adding it..
I got 69 errors =x

1>------ Build started: Project: TestCURL, Configuration: Debug Win32 ------
1>Linking...
1>libcurl.lib(easy.obj) : error LNK2019: unresolved external symbol __imp__WSACleanup@0 referenced in function _win32_init
1>libcurl.lib(telnet.obj) : error LNK2001: unresolved external symbol __imp__WSACleanup@0
1>libcurl.lib(easy.obj) : error LNK2019: unresolved external symbol __imp__WSAStartup@8 referenced in function _win32_init
1>libcurl.lib(telnet.obj) : error LNK2001: unresolved external symbol __imp__WSAStartup@8
1>libcurl.lib(ftp.obj) : error LNK2001: unresolved external symbol __imp__closesocket@4
1>libcurl.lib(http.obj) : error LNK2001: unresolved external symbol __imp__closesocket@4
1>libcurl.lib(url.obj) : error LNK2019: unresolved external symbol __imp__closesocket@4 referenced in function _conn_free
1>libcurl.lib(transfer.obj) : error LNK2001: unresolved external symbol __imp__closesocket@4
1>libcurl.lib(connect.obj) : error LNK2001: unresolved external symbol __imp__closesocket@4
1>libcurl.lib(hostthre.obj) : error LNK2001: unresolved external symbol __imp__closesocket@4
1>libcurl.lib(tftp.obj) : error LNK2001: unresolved external symbol __imp__WSAGetLastError@0
1>libcurl.lib(telnet.obj) : error LNK2001: unresolved external symbol __imp__WSAGetLastError@0
1>libcurl.lib(ftp.obj) : error LNK2019: unresolved external symbol __imp__WSAGetLastError@0 referenced in function _ftp_parse_url_path
1>libcurl.lib(select.obj) : error LNK2001: unresolved external symbol __imp__WSAGetLastError@0
1>libcurl.lib(transfer.obj) : error LNK2001: unresolved external symbol __imp__WSAGetLastError@0
1>libcurl.lib(sendf.obj) : error LNK2001: unresolved external symbol __imp__WSAGetLastError@0
1>libcurl.lib(connect.obj) : error LNK2001: unresolved external symbol __imp__WSAGetLastError@0
1>libcurl.lib(hostthre.obj) : error LNK2001: unresolved external symbol __imp__WSAGetLastError@0
1>libcurl.lib(sendf.obj) : error LNK2019: unresolved external symbol __imp__send@16 referenced in function _Curl_send_plain
1>libcurl.lib(telnet.obj) : error LNK2001: unresolved external symbol __imp__send@16
1>libcurl.lib(sendf.obj) : error LNK2019: unresolved external symbol __imp__recv@16 referenced in function _Curl_recv_plain
1>libcurl.lib(connect.obj) : error LNK2001: unresolved external symbol __imp__recv@16
1>libcurl.lib(connect.obj) : error LNK2019: unresolved external symbol __imp__getsockname@12 referenced in function _Curl_updateconninfo
1>libcurl.lib(ftp.obj) : error LNK2001: unresolved external symbol __imp__getsockname@12
1>libcurl.lib(connect.obj) : error LNK2019: unresolved external symbol __imp__getpeername@12 referenced in function _Curl_updateconninfo
1>libcurl.lib(connect.obj) : error LNK2019: unresolved external symbol __imp__ntohs@4 referenced in function _getaddressinfo
1>libcurl.lib(ftp.obj) : error LNK2001: unresolved external symbol __imp__ntohs@4
1>libcurl.lib(socks.obj) : error LNK2001: unresolved external symbol __imp__ntohs@4
1>libcurl.lib(connect.obj) : error LNK2019: unresolved external symbol __imp__getsockopt@20 referenced in function _verifyconnect
1>libcurl.lib(connect.obj) : error LNK2019: unresolved external symbol __imp__setsockopt@20 referenced in function _Curl_sndbufset
1>libcurl.lib(connect.obj) : error LNK2019: unresolved external symbol __imp__connect@12 referenced in function _singleipconnect
1>libcurl.lib(connect.obj) : error LNK2019: unresolved external symbol __imp__socket@12 referenced in function _singleipconnect
1>libcurl.lib(hostthre.obj) : error LNK2001: unresolved external symbol __imp__socket@12
1>libcurl.lib(ftp.obj) : error LNK2001: unresolved external symbol __imp__socket@12
1>libcurl.lib(connect.obj) : error LNK2019: unresolved external symbol __imp__bind@12 referenced in function _bindlocal
1>libcurl.lib(tftp.obj) : error LNK2001: unresolved external symbol __imp__bind@12
1>libcurl.lib(ftp.obj) : error LNK2001: unresolved external symbol __imp__bind@12
1>libcurl.lib(connect.obj) : error LNK2019: unresolved external symbol __imp__htons@4 referenced in function _bindlocal
1>libcurl.lib(curl_addrinfo.obj) : error LNK2001: unresolved external symbol __imp__htons@4
1>libcurl.lib(ftp.obj) : error LNK2001: unresolved external symbol __imp__htons@4
1>libcurl.lib(socks.obj) : error LNK2001: unresolved external symbol __imp__htons@4
1>libcurl.lib(curl_addrinfo.obj) : error LNK2019: unresolved external symbol __imp__freeaddrinfo@4 referenced in function _Curl_getaddrinfo_ex
1>libcurl.lib(curl_addrinfo.obj) : error LNK2019: unresolved external symbol __imp__getaddrinfo@16 referenced in function _Curl_getaddrinfo_ex
1>libcurl.lib(smtp.obj) : error LNK2019: unresolved external symbol __imp__gethostname@8 referenced in function _smtp_connect
1>libcurl.lib(tftp.obj) : error LNK2019: unresolved external symbol __imp__sendto@24 referenced in function _tftp_send_first
1>libcurl.lib(tftp.obj) : error LNK2019: unresolved external symbol __imp__recvfrom@24 referenced in function _tftp_receive_packet
1>libcurl.lib(ldap.obj) : error LNK2019: unresolved external symbol __imp__ldap_unbind_s referenced in function _Curl_ldap
1>libcurl.lib(ldap.obj) : error LNK2019: unresolved external symbol __imp__ldap_msgfree referenced in function _Curl_ldap
1>libcurl.lib(ldap.obj) : error LNK2019: unresolved external symbol __imp__ber_free referenced in function _Curl_ldap
1>libcurl.lib(ldap.obj) : error LNK2019: unresolved external symbol __imp__ldap_memfree referenced in function _Curl_ldap
1>libcurl.lib(ldap.obj) : error LNK2019: unresolved external symbol __imp__ldap_value_free_len referenced in function _Curl_ldap
1>libcurl.lib(ldap.obj) : error LNK2019: unresolved external symbol __imp__ldap_get_values_len referenced in function _Curl_ldap
1>libcurl.lib(ldap.obj) : error LNK2019: unresolved external symbol __imp__ldap_next_attribute referenced in function _Curl_ldap
1>libcurl.lib(ldap.obj) : error LNK2019: unresolved external symbol __imp__ldap_first_attribute referenced in function _Curl_ldap
1>libcurl.lib(ldap.obj) : error LNK2019: unresolved external symbol __imp__ldap_get_dn referenced in function _Curl_ldap
1>libcurl.lib(ldap.obj) : error LNK2019: unresolved external symbol __imp__ldap_next_entry referenced in function _Curl_ldap
1>libcurl.lib(ldap.obj) : error LNK2019: unresolved external symbol __imp__ldap_first_entry referenced in function _Curl_ldap
1>libcurl.lib(ldap.obj) : error LNK2019: unresolved external symbol __imp__ldap_search_s referenced in function _Curl_ldap
1>libcurl.lib(ldap.obj) : error LNK2019: unresolved external symbol __imp__ldap_simple_bind_s referenced in function _Curl_ldap
1>libcurl.lib(ldap.obj) : error LNK2019: unresolved external symbol __imp__ldap_init referenced in function _Curl_ldap
1>libcurl.lib(ldap.obj) : error LNK2019: unresolved external symbol __imp__ldap_set_option referenced in function _Curl_ldap
1>libcurl.lib(ldap.obj) : error LNK2019: unresolved external symbol __imp__ldap_err2string referenced in function _Curl_ldap
1>libcurl.lib(ftp.obj) : error LNK2019: unresolved external symbol __imp__listen@8 referenced in function _ftp_state_use_port
1>libcurl.lib(ftp.obj) : error LNK2019: unresolved external symbol __imp__accept@12 referenced in function _AllowServerConnect
1>libcurl.lib(select.obj) : error LNK2019: unresolved external symbol ___WSAFDIsSet@8 referenced in function _Curl_socket_ready
1>libcurl.lib(select.obj) : error LNK2019: unresolved external symbol __imp__select@20 referenced in function _Curl_socket_ready
1>libcurl.lib(select.obj) : error LNK2019: unresolved external symbol __imp__WSASetLastError@4 referenced in function _wait_ms
1>libcurl.lib(nonblock.obj) : error LNK2019: unresolved external symbol __imp__ioctlsocket@12 referenced in function _curlx_nonblock
1>C:\MyFirstAttempt\curl-7.21.0\TestCURL\Debug\TestCURL.exe : fatal error LNK1120: 42 unresolved externals
1>Build log was saved at "file://c:\MyFirstAttempt\curl-7.21.0\TestCURL\Debug\BuildLog.htm"
1>TestCURL - 69 error(s), 0 warning(s)
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

I know I'm definitely missing some dll or lib file this time, too.
Since the error messages are about the same.
Just.. In larger quantities now =/

 

[celerisk]

WSA... and friends means a missing socket library.
ws2_32.lib (I think... google it )

For the "ldap" errors: wldap32.lib (probably) - what you need ldap for?

 

[SineCosine]

Holy ****
Adding those 2 libraries solved all 69 errors ._.
How do you remember all this?

You must've spent at least 5 lifetimes programming O_O
I am awed again.

[EDIT]
I'm now reading up on all the functions libcurl has <.<
What's the difference between curl_easy_init() and curl_share_init() ?
Also, it returns.. what exactly?

A.. CURL *handle?
Is it an instance of a connection or something like that? o.0

[EDIT=2]
Any idea why this won't work?
Yea, I'm just playing around with it for now =x

// TestCURL.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <curl.h>
#include <iostream>
#include <stdio.h>
#include <string>
#include <sstream>

using namespace std;

int main () {
  CURL *curl;
  CURLcode res;
  string test;
  
  cout<< "Enter a Web Address: ";
  getline(cin, test);
 
  curl = curl_easy_init();
  if(curl) {
	  curl_easy_setopt(curl, CURLOPT_URL, test); //This does not work.
    res = curl_easy_perform(curl);
 
    /* always cleanup */ 
    curl_easy_cleanup(curl);
  }
  return 0;

}

[EDIT=3]
Yessah!
Woot!

Celerisk!
You've done it again!
You helped me out BIG TIME!
YESSAH!!!

It worked!
WORKED!!!!

I am happyyyyyyyy~~~
Now I need to figure out how to read and write from a text file -____-

[EDIT]
The form was sent with libcurl!
La dee da!!!
This feels gooooood

 

[celerisk]

" Is it an instance of a connection "

Close enough.

From your example:
curl_easy_setopt(curl, CURLOPT_URL, test)

This adds "test" as "URL" to "curl".
For this to work, curl needs to be... well, something that makes sense to the library.
That sense comes from the init call.


You noticed that libcurl offers a multi interface?
As the doc puts it:
" Enable multiple simultaneous transfers in the same thread without making it complicated for the application "

 

[SineCosine]

Transfers.. In the same thread? o.0
You mean multiple "curl_easy_setopt(curl, CURLOPT_URL, parameter)"s at one go?

So.. using..
curl_multi_add_handle(Some *curl easy handle.. )
curl_multi_perform()

???
But curl_easy_setopt does not return any.. handles.

 

[celerisk]

Have you considered a look at the provided examples?

Basic "save headers":
http://curl.haxx.se/libcurl/c/sepheaders.html

Example of "multi" requests:
http://curl.haxx.se/libcurl/c/multi-app.html

 

[SerraAvenger]

Just out of interest, why would you ever do something like that in C++?
Why not ruby/RoR?
I think golang is nice for such stuff too.

 

[celerisk]

" why would you ever do something like that in C++? "

Speed.
C / C++ is the only guaranteed way to get this to wire-speed
And you do want wire-speed on something as significant as spamming unsuspecting Internet users.


Why he is going for it, I do not know.

 

[Lyerae]

Forget about speed. If your so concerned with speed, code in machine language.

 

[codemonkey]

PHP with APC and memcache is as fast as C.

 

[SerraAvenger]

The main speed issue in here is connection speed.

 

[The Helper]

Hall of Fame!