C++ program will not start when trying to redirect console output to text file

Question

I am trying to run a C++ program and redirect the console output to a text file. From my understanding, this is achieved by:

./program > console.txt

I am able to compile and run the program using ./program fine and get the console output I am expecting. When I run ./program > console.txt nothing happens, I simply enter a linebreak and am on a new line in my console input (looks like the following)

$ ./program > console.txt

I have also tried append instead of redirect using ./program >> console.txt, as well as ./program | tee console.txt.

I know I can alter the C++ program to write to a file using <fstream> but I'd like to figure out why the redirect is not starting the program.

Thanks in advance!

Perhaps your program is writing to stderr, not stdout? Does ```./program 2> console.txt``` work? — user2233706, Apr 26 '21 at 04:41
When you say "nothing happens" perhaps the program is waiting for *input*? You only redirect the standard output, you still need to provide input if your program reads from standard input. — Some programmer dude, Apr 26 '21 at 04:42
@user2233706 That worked perfectly it's running as expected now. Thanks a bunch! — christohew, Apr 26 '21 at 04:45
See [What is the difference between cout, cerr, clog of iostream header in c++? When to use which one?](https://stackoverflow.com/questions/16772842/what-is-the-difference-between-cout-cerr-clog-of-iostream-header-in-c-when) — Some programmer dude, Apr 26 '21 at 05:13

score 1 · Accepted Answer · answered Apr 26 '21 at 04:59

1

If you are redirecting to stderr, do ./program 2> console.txt. 2 is the file descriptor number for stderr.

stderr should only be used for error output.

answered Apr 26 '21 at 04:59

user2233706

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C++ program will not start when trying to redirect console output to text file

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