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Comment by MenhirMike | Hacker News Reader

I do like that /bin/true can actually fail and return false, which technically makes a "Not /bin/false" invocation more resilient: https://github.com/coreutils/coreutils/blob/master/src/true.... (and yes, I know it's the most unlikely thing, I just found it funny)

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The other interesting thing about the true command is how much more complicated it got then it needed to be.

first an exercise

  touch mytrue
  chmod u+x mytrue
  ./mytrue
  echo "error code for mytrue is $?"

This is literally how true started life. yes it is very zen.

The first offense was legal. All code had to have a copyright disclaimer. even an empty file? Yes. so now it was a file with a copyright disclaimer and nothing else. And the koan-like question comes to mind is "Can you copyright nothing?" well AT&T sure tried.

Then somebody said our programs should be well defined and not depend on a fluke of unix, which at this point was probably a good idea. So true finally had code. It was "exit 0"

Then somebody said we should write our system utilities in C instead of shell so it runs faster. openbsd still has a good example of how this would look.

http://cvsweb.openbsd.org/cgi-bin/cvsweb/~checkout~/src/usr....

At some point gnu bureaucracy got involved and said all programs must support the '-h' flag. so that got added, then they said all programs must support locale so that got added. now days gnu true is an astonishing 80 lines long.

https://github.com/coreutils/coreutils/blob/master/src/true....

Which is fine I guess, but that is a lot of code for a program that by definition "Does nothing, successfully"

http://trillian.mit.edu/~jc/humor/ATT_Copyright_true.html

Only if run with options, right? It looks like just running `true` is unaffected unless the comment is misleading me.

Yeah, I don't see it either. If being run without --help or --version, true can only ever return EXIT_SUCCESS.

However, I find it interesting that true and false use the very same implementation.

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