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+ + + +
+true(1) is a tool that only quits silently with an exit status of 0.
+Similarly, false(1) is a tool that only quits silently with an exit status of 1.
+Recognizing arguments, printing to standard output, reading from standard input, or otherwise exiting with any other status of 0, is a violation of the POSIX specification for true(1).
+These utilities find use in shell scripting, which, though extremely relevant to these utilities, is beyond the scope of this article.
+
+Because true(1)'s required functionality is so simple a POSIX-compliant implementation is a one-liner in most languages, so long as you're willing to make an exception in your code styling.
+For example, in C:
+
+int main(void) { return 0; }
+
+Because executing an empty shellscript file will in most shells do nothing and return an exit status of 0, technically an empty shellscript file is a POSIX-compliant true(1) implementation in 0 bytes.
+However (TODO) it's to me unknown whether this is implementation-specific or POSIX-specified.
+The usual implementation in POSIX shell is also a one-liner if you ignore the shebang:
+
+#!/bin/sh
+exit 0
++This happens to be nearly identical in source to the implementation used by NetBSD. +
+
+Here's false(1) in Python rather than true(1) to demonstrate how exiting with an arbitrary exit status can be done:
+
+import sys
+sys.exit(1)
+
+In some shells, true(1) is a shell built-in command, so running true will run the shell author's implementation of true(1) rather than the system implementation.
+
+GNU true(1), from the GNU coreutils, deserves a special mention, as it's eighty lines long and directly includes four C header files.
+This is not a joke.
+Their true.c is 2.3 kilobytes, parses the arguments --help and --version (only if either are the first argument to the program), and I don't know how big the executable ends up being because the first thing I do when I take control of a GNU system is printf "#/bin/sh\nexit 0\n"|dd of="$(which true)";chmod +x "$(which true)" (use at your own risk).
+