So I have some decoded text which I have to write as binary in a new file.
I came up with this code but it writes it as a decoded text instead of binary
#include <iostream>
#include <fstream>
#include <string>
#include <sstream>
#include <cctype>
#include <locale>
#include <vector>
#include <iterator>
#include <iomanip>
using namespace std;
int main() {
ofstream outputFile;
outputfile.open("binary.dat");
ifstream file("binary.dat", ios::binary);
outputfile <<"68656C6C6F20776F726C64";
return 0;
}
Thank you for any help!
You have to open the file in binary mode to write binary data
outputfile.open("binary.dat", ofstream::binary)
Note: This is assuming you are intending to simply write the binary representation of your text string, rather than treat your string as hexadecimal values as was mentioned in the comments
Related
I'm trying to print the text "Ääkkösiä ruutuun." to console with c++. I have windows 7 and am using Code::Blocks editor. Searching on the subject I found that maybe these sort of lines would help
_setmode(_fileno(stdout), _O_U16TEXT);
wstring s{L"Ääkkösiä ruutuun."};
wcout<<s<<endl;
But when I try to compile it, I get the error: _fileno was not declared in this scope.
I have all these includes:
#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <map>
#include <set>
#include <stdexcept>
#include <cmath>
#include <sstream>
#include <fstream>
#include <codecvt>
#include <locale>
#include <fcntl.h>
#include <io.h>
#include <stdio.h>
#include <cstdio>
#include <ostream>
what am I missing?
Also, one other thing I tried was locale, but then locale::empty wasn't found! Why doesn't my c++ have anything in it?
EDIT
Here is a picture of what my program is doing now.
It prints out just the first letter (Ä). What happens to the rest?
Ok, it seems that setmode sets it so that only one letter gets printed. (Even trying to print normal texts with multiple commands, just results in a single letter.) Without it the scandinavian letters don't print correctly, thought. They look like this:
The answer you found is for Visual Studio, not Code::Blocks.
While the C standard specifies what should in in <stdio.h>, it only specifies a minimum. Implementors may add their own functions, and should do so using an _ (underscore prefix). This is why you should NOT use that prefix. You don't know what you'll break. Microsoft clearly signaled their non-standard extensions using the correct prefix.
The answer is tagged C++, but C++ inherits the contents of <stdio.h> from C.
The line
setlocale(LC_CTYPE, ".OCP");
works!
A complete example:
#include <iostream>
#include <fstream>
#include <string>
#include <sstream>
#include <fstream>
using namespace std;
wstring readFile(const char* filename) {
wifstream wif(filename);
locale myLoc("");
//locale utf8_locale(locale(), new gel::stdx::utf8cvt<true>);
wif.imbue(myLoc);
basic_stringstream<wchar_t> wss;
wss << wif.rdbuf();
return wss.str();
}
int main() {
setlocale(LC_CTYPE, ".OCP");
wstring contents = readFile("test.txt");
wcout<<L"Does anything get printed out at all???"<<endl;
//wcout <<contents<<endl;
wstring s{L"Ääkkösiä ruutuun."};
wcout<<s<<endl;
wcout<<L"Näkyykö äkköset?"<<endl;
return 0;
}
The text read from file (utf-8) still doesn't print correctly, though.
It should be
Hei!
Täällä on kaksi riviä.
ä's go awry there.
Output:
...Am trying to load/capture the output of system(char* command) function to a variable, a vector. can i have any possible way to push the output to my vector? I don*t want to write the output to file and read it again.
Sample code:
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fstream>
#include <iostream>
#include <string>
#include <cstring>
#include <sstream>
#include <vector>
using namespace std;
int main()
{
vector <string> dir;
system("pwd");//here i used this to print the current directory, and i want to store this out put to my vector. something like...(below )
output=output of system("pwd");//this is not a real code,just to notice i want to put the out put to other var and push.
dir.push_back(output);
return 0;
}
Can i have any scenario to do this task, thanks.
I'd recommend doing it like this:
FILE *fp = popen("fortune","r");
char line[200];
while(!feof(fp)) {
fgets(line,200,fp);
// process here
}
pclose(fp);
If it's really performance critical it's probably better to
create a child process using fork() and pipes for stdin/stdout of that child
process to write or read from.
An example of this could be found here (http://www.microhowto.info/howto/capture_the_output_of_a_child_process_in_c.html#idp21888) if you're intested. But the popen method is probably the most simple and straightforward one in your case.
I am trying to read a file which is placed in the desktop through C++ program in linux server.I have mentioned the path correctly,but it's not reading the file. I have tried the same program in windows platform it's working fine.I'm able to read the file.
#include <stdio.h>
#include <fstream>
#include <stdlib.h>
#include <string>
#include <iostream>
#include <cstring>
using namespace std;
int main()
{
string line;
ifstream file;
file.open("/home/xxx/Desktop/nodeinfo.txt",ios::in);
if(!file.is_open())
{
cout<<"error";
}
getline(file,line);
cout<<line;
return 0;
}
could someone help me how to solve this problem. Is there any specific path format for linux platform. Thanks
I am experimenting with CGI in C++. I know that there are libraries which handle basic stuff, but in order to know whats going on under the hood i have been trying to parse the stdin using string datatype ---> tokenize using '= and &' then push_back into a vector. at the latter step, i am receiving segmentation fault. given below is the program where i am using cin>> to obtain user input and so on ..
#include <iostream>
#include <stdlib.h>
#include <stdio.h>
#include <vector>
#include <algorithm>
#include <string.h>
using namespace std;
int main()
{
vector <string> stuff(0);
vector<string>::iterator it;
char* bufferchar;
string buffer;
char str[size];
cout<<"Content-type: text/html\n\n"
<<"<html>"
<<"<head>"
<<"<title>CGI SCRIPT</title>"
<<"</head>"
<<"<body>"
fgets(str,20,stdin); //20 is expect size of content from html form
puts(str);
cout<<"<p>Now to break this guy apart";
int x=0;
bufferchar = strtok(str,"&=");
buffer+=bufferchar;
stuff.push_back(buffer);
while(bufferchar!=NULL){
cout<<bufferchar<<'\n'<<'\n';
bufferchar=strtok(NULL,"&=");
buffer+=bufferchar;
stuff.push_back(buffer);
}
cout<<"<br>ok does the vector iterate ?";
for (it=stuff.begin();it!=stuff.end();++it){
cout<<*it;
cout<<"<br> ok man, next <br><br>";
}
cout<<"</body>";
cout<<"</html>";
}
I am trying to read a .gz file and print the text content on screen by using boost::iostreams. This is just a simple experiment to learn about this library, and I am using the "directors.list.gz" file from IMDb (ftp://ftp.fu-berlin.de/pub/misc/movies/database/) as my input file.
My code compiles, via MSVC-10, but the process aborts when executed. There's not much information from the error message except for the error code being R6010.
Can someone please point me a direction in terms of what may have caused this and how do I make this work?
This library looks pretty neat and I do hope to use it correctly. Thanks a lot for helping.
#include <fstream> // isalpha
#include <iostream> // EOF
#include <boost/iostreams/categories.hpp> // input_filter_tag
#include <boost/iostreams/operations.hpp> // get
#include <boost/iostreams/filtering_stream.hpp>
#include <boost/iostreams/copy.hpp>
#include <boost/iostreams/device/file_descriptor.hpp>
#include <boost/iostreams/device/file.hpp>
#include <boost/iostreams/device/array.hpp>
#include <boost/iostreams/filter/zlib.hpp>
using namespace std;
namespace io = boost::iostreams;
int main()
{
if(true)
{
string infile_path = "c:\\Temp\\directors.list.gz";
ifstream infile(infile_path, ios_base::in | ios_base::binary);
io::filtering_streambuf<io::input> in; //filter
in.push(io::zlib_decompressor());
in.push(infile);
//output to cout
io::copy(in, cout);
}
return 0;
}
The gzip file format has an additional header around the zlib data, which zlib can't read.
So you want to use boost's gzip_decompressor instead of zlib_decompressor.
in.push(gzip_decompressor());
Note you'll need to include boost/iostreams/filter/gzip.h instead of boost/iostreams/filter/zlib.h.
Here's a working example of streaming a GZIP file:
#include <fstream>
#include <iostream>
#include <boost/iostreams/filtering_streambuf.hpp>
#include <boost/iostreams/filter/gzip.hpp>
#include <boost/iostreams/copy.hpp>
using namespace boost::iostreams;
int main()
{
std::ifstream file("hello.gz", std::ios_base::in | std::ios_base::binary);
filtering_streambuf < input > in;
in.push(gzip_decompressor());
in.push(file);
boost::iostreams::copy(in, std::cout);
}
You'll find more information on specific boost::iostreams filters lurking here in boost's documentation: http://www.boost.org/doc/libs/1_46_1/libs/iostreams/doc/quick_reference.html#filters
I also feel I should point out that your code didn't compile with gcc: in the C++ standard library, the ifstream constructor takes a const char *, not a std::string. (I'm not sure about Microsoft's version).