UNIX Utilities II: True and False

It is occasionally useful to check the outputs of commands in bash scripts; it is even more useful to test your scripts for all eventualities before you release them, to make sure strange errors don't begin occurring once they have been run in a variety of environments; this is where "true" and "false" come in.

These two simple programs simply return 0, or 1 as an exit status when run. This is probably the only case in a UNIX system where you will see 1 denoting a success.

Once compiled, these programs end up being about 8.3 kb on my system, which is almost a third the size of the GNU versions, how this happened, I have no idea; they are in essence the simplest programs in the world:

/**
 * true - Probably the simplest program in the world, does nothing, and
 * succeeds at it. Not very realistic, I know, but this is UNIX after 
 * all, not the real world where not doing anything makes you a failure.
 * 
 * Copyright 2011-12-23 Joseph Lewis <joehms22@gmail.com>
 */

int main()
{
 return 0;
}

/**
 * false
 * Probably the (second) simplest program in the world, does nothing, 
 * and fails at it. Note that this is the second because "true" is the 
 * first.
 * 
 * Copyright 2011-12-23 Joseph Lewis <joehms22@gmail.com>
 */

int main()
{
 return 1; // FAIL
}