Online CPP Compiler that allows writing/reading

Question

I am trying to write out data and read it back in on ideone.com. I could not figure it out:

ofstream os ("data.dat", ios::binary);

did not work, when I try to read back in with

ifstream is("data.dat", ios::binary);

the size of the data read is 0.

Is there a different syntax at online compilers, such as ideone.com?

Why are C++ Coders always so unforgiving? Is it the typedef? — user1767754, Mar 29 '16 at 12:17
I'm sorry it's so unforgiving to uphold the rule you broke with the first revision. The question is better than before. — chris, Mar 29 '16 at 12:22
@user1767754 The question you need to ask is why are other tags so lenient on the quality standards ;) — NathanOliver, Mar 29 '16 at 12:22
@chris education doesn't work by punishing, it works by commenting. Thats what other users tried. — user1767754, Mar 29 '16 at 12:25
It's not a punishment. The site's terms are that you ask an [on-topic](http://stackoverflow.com/help/on-topic) question and people will most likely answer it. There are two sides to that. Punishment for not meeting your end would go beyond us not meeting ours. — chris, Mar 29 '16 at 12:29

score 2 · Accepted Answer · edited May 23 '17 at 12:31

Most if not all online compilers that I have seen do not allow you to read and write to files. Most allow you to input text into an input box and then they redirect the standard input to that box so you can change the input to the program from run to run.

Reading this answer by Shafik Yaghmour and the attached documentation it looks like you can create a file with coliru and then use that file in a subsequent program but I have no idea how well that will work with a binary file and it looks like it might be read only.

I would think most services do want to allow file uploads as then people could upload to there service and then the site could be hosting some undesirable content.

If you need to work with files I suggest you use an actual compiler on your PC. If you need something that is free then you can start at Bjarne Stroustrup's An incomplete list of C++ compilers

Online CPP Compiler that allows writing/reading

1 Answers1