# 15. Software Version Numbers

PRRTE’s version numbers are the union of several different values: major, minor, release, and an optional quantifier.

- Major: The major number is the first integer in the version string (e.g., v1.2.3). Changes in the major number typically indicate a significant change in the code base and/or end-user functionality. The major number is always included in the version number.

- Minor: The minor number is the second integer in the version string (e.g., v1.2.3). Changes in the minor number typically indicate a incremental change in the code base and/or end-user functionality. The minor number is always included in the version number:

- Release: The release number is the third integer in the version string (e.g., v1.2.3). Changes in the release number typically indicate a bug fix in the code base and/or end-user functionality.

- Quantifier: PRRTE version numbers sometimes have an arbitrary string affixed to the end of the version number. Common strings include:

  - `aX`: Indicates an alpha release. X is an integer indicating the number of the alpha release (e.g., v1.2.3a5 indicates the 5th alpha release of version 1.2.3).

  - `bX`: Indicates a beta release. X is an integer indicating the number of the beta release (e.g., v1.2.3b3 indicates the 3rd beta release of version 1.2.3).

  - `rcX`: Indicates a release candidate. X is an integer indicating the number of the release candidate (e.g., v1.2.3rc4 indicates the 4th release candidate of version 1.2.3).

Although the major, minor, and release values (and optional quantifiers) are reported in PRRTE snapshot tarballs, the filenames of these snapshot tarballs follow a slightly different convention.

Specifically, the snapshot tarball filename contains three distinct values:

- Most recent Git tag name on the branch from which the tarball was created.

- An integer indicating how many Git commits have occurred since that Git tag.

- The Git hash of the tip of the branch.

For example, a snapshot tarball filename of `prrte-v1.0.2-57-gb9f1fd9.tar.bz2` indicates that this tarball was created from the v1.0 branch, 57 Git commits after the `v1.0.2` tag, specifically at Git hash gb9f1fd9.

PRRTE’s Git master branch contains a single `dev` tag. For example, `prrte-dev-8-gf21c349.tar.bz2` represents a snapshot tarball created from the master branch, 8 Git commits after the “dev” tag, specifically at Git hash gf21c349.

The exact value of the “number of Git commits past a tag” integer is fairly meaningless; its sole purpose is to provide an easy, human-recognizable ordering for snapshot tarballs.