[orig. from BASIC's 'CHAIN' statement]
vi. To hand off
execution to a child or successor without going through the
OS command interpreter that invoked it. The state of the
parent program is lost and there is no returning to it. Though
this facility used to be common on memory-limited micros and is
still widely supported for backward compatibility, the jargon usage
is semi-obsolescent; in particular, most UNIX programmers will
think of this as an exec.
Oppose the more modern subshell.
