Question

I have a peculiar problem. I have a Java program that is run with the command :

cat input_file_name | ./script_name > file_output_name

the script_name script just does : java myprogram

My question is : how can I print out something in the console without it being “put in the file_output_name file” (since the > file puts all System.out.prints in that file)

I know this is possible because there are some already that come from some class in a library that I’m using from my java program. However I can’t find the exact source of those prints so I don’t know how it is coded.

Thank you for any help.

Answer 1

The easiest way is to use System.err.println() instead of System.out.

It will go to a different “device” (stderr instead of stdout), and it won’t be redirected.