bool CopyFileContents(std::string source, std::string target)
{
	FILE *sourcefile = fopen(source.c_str(), "rb");
	if(sourcefile == NULL){
		errorstream<<source<<": can't open for reading: "
			<<strerror(errno)<<std::endl;
		return false;
	}

	FILE *targetfile = fopen(target.c_str(), "wb");
	if(targetfile == NULL){
		errorstream<<target<<": can't open for writing: "
			<<strerror(errno)<<std::endl;
		fclose(sourcefile);
		return false;
	}

	size_t total = 0;
	bool retval = true;
	bool done = false;
	while(!done){
		char readbuffer[BUFSIZ];
		size_t readbytes = fread(readbuffer, 1,
				sizeof(readbuffer), sourcefile);
		total += readbytes;
		if(ferror(sourcefile)){
			errorstream<<source<<": IO error: "
				<<strerror(errno)<<std::endl;
			retval = false;
			done = true;
		}
		if(readbytes > 0){
			fwrite(readbuffer, 1, readbytes, targetfile);
		}
		if(readbytes != sizeof(readbuffer)){
			// EOF or error on read (error case was handled above)
			// flush destination file to catch write errors
			fflush(targetfile);
			done = true;
		}
		if(ferror(targetfile)){
			errorstream<<target<<": IO error: "
					<<strerror(errno)<<std::endl;
			retval = false;
			done = true;
		}
	}
	infostream<<"copied "<<total<<" bytes from "
		<<source<<" to "<<target<<std::endl;
	fclose(sourcefile);
	fclose(targetfile);
	return retval;
}