How do I open a URL from C++? - html

Question

how can I open a URL from my C++ program?
In ruby you can do
%x(open https://google.com)
What's the equivalent in C++? I wonder if there's a platform-independent solution. But if there isn't, I'd like the Unix/Mac better :)
Here's my code:
#include <stdio.h>
#include <string.h>
#include <fstream>
int main (int argc, char *argv[])
{
char url[1000] = "https://www.google.com";
std::fstream fs;
fs.open(url);
fs.close();
return 0;
}

Answer 1

Your question may mean two different things:
1.) Open a web page with a browser.
#include <windows.h>
#include <shellapi.h>
...
ShellExecute(0, 0, L"http://www.google.com", 0, 0 , SW_SHOW );
This should work, it opens the file with the associated program. Should open the browser, which is usually the default web browser.
2.) Get the code of a webpage and you will render it yourself or do some other thing. For this I recommend to read this or/and this.
I hope it's at least a little helpful.
EDIT: Did not notice, what you are asking for UNIX, this only work on Windows.

Answer 2

Use libcurl, here is a simple example.
EDIT: If this is about starting a web browser from C++, you can invoke a shell command with system on a POSIX system:
system("<mybrowser> http://google.com");
By replacing <mybrowser> with the browser you want to launch.

Answer 3

Here's an example in windows code using winsock.
#include <winsock2.h>
#include <windows.h>
#include <iostream>
#include <string>
#include <locale>
#pragma comment(lib,"ws2_32.lib")
using namespace std;
string website_HTML;
locale local;
void get_Website(char *url );
int main ()
{
//open website
get_Website("www.google.com" );
//format website HTML
for (size_t i=0; i<website_HTML.length(); ++i)
website_HTML[i]= tolower(website_HTML[i],local);
//display HTML
cout <<website_HTML;
cout<<"\n\n";
return 0;
}
//***************************
void get_Website(char *url )
{
WSADATA wsaData;
SOCKET Socket;
SOCKADDR_IN SockAddr;
int lineCount=0;
int rowCount=0;
struct hostent *host;
char *get_http= new char[256];
memset(get_http,' ', sizeof(get_http) );
strcpy(get_http,"GET / HTTP/1.1\r\nHost: ");
strcat(get_http,url);
strcat(get_http,"\r\nConnection: close\r\n\r\n");
if (WSAStartup(MAKEWORD(2,2), &wsaData) != 0)
{
cout << "WSAStartup failed.\n";
system("pause");
//return 1;
}
Socket=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);
host = gethostbyname(url);
SockAddr.sin_port=htons(80);
SockAddr.sin_family=AF_INET;
SockAddr.sin_addr.s_addr = *((unsigned long*)host->h_addr);
cout << "Connecting to "<< url<<" ...\n";
if(connect(Socket,(SOCKADDR*)(&SockAddr),sizeof(SockAddr)) != 0)
{
cout << "Could not connect";
system("pause");
//return 1;
}
cout << "Connected.\n";
send(Socket,get_http, strlen(get_http),0 );
char buffer[10000];
int nDataLength;
while ((nDataLength = recv(Socket,buffer,10000,0)) > 0)
{
int i = 0;
while (buffer[i] >= 32 || buffer[i] == '\n' || buffer[i] == '\r')
{
website_HTML+=buffer[i];
i += 1;
}
}
closesocket(Socket);
WSACleanup();
delete[] get_http;
}

Answer 4

I was having the exact same problem in Windows.
I noticed that in OP's gist, he uses string("open ") in line 21, however, by using it one comes across this error:
'open' is not recognized as an internal or external command
After researching, I have found that open is MacOS the default command to open things. It is different on Windows or Linux.
Linux: xdg-open <URL>
Windows: start <URL>
For those of you that are using Windows, as I am, you can use the following:
std::string op = std::string("start ").append(url);
system(op.c_str());

Answer 5

I've had MUCH better luck using ShellExecuteA(). I've heard that there are a lot of security risks when you use "system()". This is what I came up with for my own code.
void SearchWeb( string word )
{
string base_URL = "http://www.bing.com/search?q=";
string search_URL = "dummy";
search_URL = base_URL + word;
cout << "Searching for: \"" << word << "\"\n";
ShellExecuteA(NULL, "open", search_URL.c_str(), NULL, NULL, SW_SHOWNORMAL);
}
p.s. Its using WinAPI if i'm correct. So its not multiplatform solution.

Answer 6

There're already answers for windows. In linux, I noticed open https://www.google.com always launch browser from shell, so you can try:
system("open https://your.domain/uri");
that's say
system(("open "s + url).c_str()); // c++
https://linux.die.net/man/1/open

Answer 7

C isn't as high-level as the scripting language you mention. But if you want to stay away from socket-based programming, try Curl. Curl is a great C library and has many features. I have used it for years and always recommend it. It also includes some stand alone programs for testing or shell use.

Answer 8

For linux environments, you can use xdg-open. It is installed by default on most distributions. The benefit over the accepted answer is that it opens the user's preferred browser.
$ xdg-open https://google.com
$ xdg-open steam://run/10
Of course you can wrap this in a system() call.

Answer 9

Create a function and copy the code using winsock which is mentioned already by Software_Developer.
For Instance:
#ifdef _WIN32
// this is required only for windows
if (WSAStartup(MAKEWORD(2,2), &wsaData) != 0)
{
//...
}
#endif
winsock code here
#ifdef _WIN32
WSACleanup();
#endif