Collect stdout output from a console app with C++

Question

I have a console application written with C++. Is there any way to collect all stdout output from it to string/pipe/memory array?

PS. I need to do this from within the console app that I'm needing to collect stdout from. Or, in other words, it is collecting from itself.

That doesn't make sense. If it's from within the app itself you already have the output, send it elsewhere. To answer the actual question, yes it's possible. Having an app that just logs stdout makes sense but I don't get where you're going with this. — evanmcdonnal
– evanmcdonnal, Commented Mar 14, 2013 at 20:33
If file output is okay, you can use freopen() to do this. See stackoverflow.com/questions/5257509/… — jxh
– jxh, Commented Mar 14, 2013 at 20:41

meyumer · Accepted Answer · 2013-03-14 20:56:35Z

Yes. To redirect it to a string, you can use a std::stringstream

std::stringstream buffer; std::streambuf * old = std::cout.rdbuf(buffer.rdbuf());

Then, if you do:

std::cout << "Example output" << std::endl; std::string text = buffer.str();

You will see that text now contains "Example output\n".

My output mostly comes from C-like calls to _tprintf(_T("Some line1\n")); that doesn't seem to be caught by your approach. Any idea why?

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