- can be used for adjusting option names between versions

- in most cases already checked valid() so don't need additional check
  for setting an existing pointer

- browser is spawned as a background process to avoid blocking the
  command-line

- allows (for example) splitting a user string on whitespace and
  passing this to system as a list of arguments, thus bypassing any
  implicit use of 'sh'.

- system() with optional background, for spawning processes.

- this makes them applicable to Foam::string, Foam::word etc

ENH: improvements to CStringList

- add strings() sublist variant which can be useful when handling
  command arguments separately

- add construct from SubStrings.

Feature multiple stitch mesh (wp04)

See merge request OpenFOAM-plus!164

Consistency update for list typedefs

See merge request OpenFOAM-plus!171

- in rare cases we may wish to have command-line arguments that are
  non-mandatory. This can now be reflected in the usage output, provided
  that the argList::nonMandatoryArgs() has been used.

- added setRootCaseNonMandatoryArgs.H that applies the
  argList::nonMandatoryArgs() settings and otherwise performs largely
  as per setRootCase.H, except that the check for mandatory arguments
  is deferred to later user code.

- constructor for empty cell/face/point Zones, with contents to be
  transferred in later.

- ZoneMesh::operator(const word&) to return existing zone or a new empty one.

cellModel enumerations

See merge request OpenFOAM-plus!170

- this provides a better typesafe means of locating predefined cell
  models than relying on strings. The lookup is now ptr() or ref()
  directly. The lookup functions behave like on-demand singletons when
  loading "etc/cellModels".

  Functionality is now located entirely in cellModel but a forwarding
  version of cellModeller is provided for API (but not ABI) compatibility
  with older existing user code.

STYLE: use constexpr for cellMatcher constants

- warn or fatal if Pstream::init or Pstream::exit are called multiple
  times.

- additional Pstream::initNull method as failsafe to initialize MPI
  when the underlying OpenFOAM process is not running in parallel but
  the application still needs MPI.

- Pstream::exit() can now also be called without having used MPI::init(),
  which means it can be used to cleanup serial process or for
  applications that used the special purpose Pstream::initNull()
  mechanism.

Mark Olesen authored 7 years ago and Mark OLESEN committed 7 years ago

- now also fixed collated output format

STYLE: use Ostream writeEntry when writing key/value entries

See merge request OpenFOAM-plus!168

- occurred when variable name exceeded the 15-char alignment format
  and the name run into the previous field.

- reduces ambiguity between matching a list of strings and a single string.

- the dictionary-driven variant of stitchMesh allows sequential
  application of 'stitch' operation with requiring intermediate
  writing to disk.

- Without arguments:
  * stitchMesh uses a system/stitchMeshDict or -dict dict

- With arguments:
  * master/slave patches specified on the command-line as in previous
    versions.

Feature function object field input

See merge request OpenFOAM-plus!167

ENH: support change of Pstream buffer format via flag modifier

See merge request OpenFOAM-plus!166

Feature field average windowing

See merge request OpenFOAM-plus!165

- allows changing the format of the sending OPstream at an arbitrary
  point in the transmission. The information is passed through the
  buffer and the receiving IPstream changes its format accordingly.
  This allows a temporary toggling of ASCII/BINARY mid-stream.

- support when creating modules for OpenFOAM.
  Original source from Ivan Spisso (CINECA) modified by OpenCFD