#include<iostream>
#include<sys/mman.h>
#include<fcntl.h>
#include<sys/stat.h>
#include<unistd.h>

std::string file_to_string(std::string filename){
	int fd = open(filename.c_str(), O_RDONLY);
	if(fd == -1){
		throw std::invalid_argument("File could not be opened");
	}
	struct stat statbuf;
	fstat(fd, &statbuf);
	char *contents = (char*)mmap(0, statbuf.st_size, PROT_READ, MAP_SHARED, fd, 0);
	std::string retval(contents);
	close(fd);
	munmap(contents, statbuf.st_size);
	return retval;
}


using namespace std;
int main(){
	try{
		cout << file_to_string("file_into_string.cpp") << endl;
	} catch (exception &e){
		cout << "Bad File\n";
	}
	return 0;
}