SPDX-License-Identifier: CC-BY-SA-4.0
copyrights:
- Copyright (C) 2021 embedded brains GmbH (http://www.embedded-brains.de)
enabled-by: true
glossary-type: term
links:
- role: glossary-member
  uid: group
term: interval
text: |
  The current interval starts with the last return from a successful call to
  ${../if/period:/name} which does not use ${../if/period-status-define:/name}
  as value for parameter ${../if/period:/params[1]/name}.  The current
  interval ends with the return from the next successful call to
  ${../if/period:/name} which does not use ${../if/period-status-define:/name}
  as value for parameter ${../if/period:/params[1]/name}.  See also
  start/end ${../glossary/deadline:/term}.

  The parameter ${../if/period:/params[1]/name} of that call specifies the
  interval length of the period.

  **Warning**: All calls to ${../if/period:/name} for the same period must
  provide the same value for parameter ${../if/period:/params[1]/name}.  That
  is, the intervals of a period must have a strictly regular length.  If that
  is not the case and the period enters ${../glossary/expired:/term}
  ${../glossary/state:/term}, future period ${../glossary/deadline:/term} are
  set arbitrarily because the use of ${../glossary/postponedjob:/plural}
  implicitly assumes a fixed time length for future
  ${../glossary/job:/plural}.

  Note, an interval denotes a time while ${../glossary/job:/term} denotes code.
  Note also, if a first call to ${../if/period:/name} which does not use
  ${../if/period-status-define:/name} returned and a second
  ${../if/period:/name} which does not use ${../if/period-status-define:/name}
  is invoked but did not yet return, the current interval is still the one of
  the first call.
type: glossary