I think the short flags are more useful when using directly the command (outside of a script). It is faster to type man grep in a window and to type grep -Eo than to type grep --extended-regexp --only-matching. At first, I even didn't realize that --extended-regexp was the same as the usual -E flag. I had to check with man.
Theoretically, I would like to agree that long flags are better than short ones in scripts. In practice, I prefer grep -E. And I can not imagine a tar cvfhz with long flags.
Theoretically, I would like to agree that long flags are better than short ones in scripts. In practice, I prefer grep -E. And I can not imagine a tar cvfhz with long flags.