OptionalpackageOptionalsingleSpecifies whether only a single package is being retrieved (true) or not (false).
If false, then more than one package is being retrieved.
OptionalspecificA list of file names to be retrieved. If a value is specified for this property, packageNames must be set to null and singlePackage must be set to true.
OptionalunpackagedA list of components to retrieve that are not in a package.
A list of package names to be retrieved. If you are retrieving only
unpackagedcomponents, do not specify a name here. You can retrievepackagedandunpackagedcomponents in the same retrieve.