C++ ofstream::open won't accept string as a filename

[chellrose]

I'm including iostream, fstream, string, and cstdlib headers. In my program, if I have



ofstream os;
string file = "infoFile.txt";

os.open(file, ios::app);


upon compilation I see the error



NoteOrganizer.cpp:28:31: error: no matching function for call to ‘std::basic_ofstream<char>::open(std::string&, const openmode&)’
NoteOrganizer.cpp:28:31: note: candidate is:
/usr/include/c++/4.6/fstream:702:7: note: void std::basic_ofstream<_CharT, _Traits>::open(const char*, std::ios_base::openmode) [with _CharT = char, _Traits = std::char_traits<char>, std::ios_base::openmode = std::_Ios_Openmode]
/usr/include/c++/4.6/fstream:702:7: note: no known conversion for argument 1 from ‘std::string {aka std::basic_string<char>}’ to ‘const char*’


but if I instead do



os.open("infoFile.txt", ios::app);


it compiles and runs just fine. I've used strings as file names countless times before, though, with no trouble at all. What is going wrong?
(BTW: I'm using g++)

Thanks! :)

[SledgeHammer_999]

As the error message says to you there isn't an open() method which accepts std::string. The open() method has this signature void open( const char *filename,
ios_base::openmode mode = ios_base::out ); So you could do:

os.open(file.c_str(), ios::app);

Or make gcc use the C++11 standard which has a suitable open() function which takes an std::string. I believe you have to use the "-std=c++11" switch when compiling.

Relevant info on open()->http://en.cppreference.com/w/cpp/io/basic_ofstream/open

[chellrose]

Right! I forgot about the c_str(). ](*,)

Thanks!

***note to all: This thread is solved... Once I figure out how to get the "prefix" option back, I'll mark it solved for real :)

[Tony Flury]

You can mark a thread as [SOLVED] by using the Thread Tools (near the top of the page).

[chellrose]

That's how I used to do it (in the old forum), but that option doesn't appear under Thread Tools now. Is there another trick that I'm missing?