= Applications and versions =

An '''application''' is an abstraction;
it includes a set of programs
(for different platforms and processor types) and a set of [JobIn jobs].
A project can operate many applications.
Applications have the following required properties:

 * Name: A short name (used to name directories, so don't use special characters like /).
 * User friendly name: the name shown to volunteers.

Optional properties:
 * Homogeneous redundancy: this application uses [HomogeneousRedundancy homogeneous redundancy].
 * Weight: the proportion of workunits of this application to be sent when the [BackendPrograms#Feeder feeder is run with the --allapps option].
 * Beta: whether jobs should be sent only to [BetaTest beta-test] users.
 * Minimum version: issue work to clients using the [http://boinc.berkeley.edu/wiki/Anonymous_platform anonymous platform mechanism]
  only if their reported application version number is this or greater.
 * Whether the application is [NonCpuIntensive non-CPU-intensive].

Applications can be created using the [XaddTool xadd] utility,
based on a description in the '''project.xml''' file.
Applications can be created or edited using the Manage Applications page of the
[HtmlOps administrative web interface].

An application program may go through a sequence of '''versions'''.
A particular version, compiled for a particular platform, is
called an '''application version'''.
An application version can consist of multiple files:
for example, a controller script, pre- and post-processing programs, and a primary program.

An application version has the following required properties:

 * Version number: an integer. Version numbers should be used consistently across platforms; Windows version 304 should be computationally identical to Mac version 304.

and the following optional properties:

 * Min and max core client version: don't send jobs to clients outside this range.
  Specified as an integer, encoded as 10000*major + 100*minor + release.

Application versions are created using [AppVersionNew update_versions].
Descriptions of application versions are stored in the '''app_version''' table in the [DataBase BOINC DB].
Application versions can be edited using the Manage Application Versions page of the
[HtmlOps administrative web interface].