The real kicker is this comment in GNU true(1). /* Note true(1) will return EXIT_FAILURE in the edge case where writes fail with GNU specific options. */

The real kicker is this comment in GNU true(1). /* Note true(1) will return EXIT_FAILURE in the edge case where writes fail with GNU specific options. */ If you can't program a bug free true(1), please stop with whatever you think you are doing.