> Input and output are also obvious. Input is what you type, output is what you see.
Input maybe, although realizing that instead of typing, you can pipe, is a major conceptual breakthrough when new users are learning to work the command line.
But output? The existence of stdout and stderr as two sources of text with no visible distinction is highly nonobvious and continues to trip me up in practical situations to this very day.
Input maybe, although realizing that instead of typing, you can pipe, is a major conceptual breakthrough when new users are learning to work the command line.
But output? The existence of stdout and stderr as two sources of text with no visible distinction is highly nonobvious and continues to trip me up in practical situations to this very day.