### 3.8 `prs`

The `prs` command (mnemonic: “print revision summary”) prints information about an SCCS file in a user-defined format. There are options for selecting which deltas are reported on; selection is possible by check-in time or by SID. The format of the output can also be specified on the command line. All parts of an SCCS file can be dumped with `prs`. Those parts which appear once per delta can be uniquely identified by SID or by time.

Typical uses for `prs` are

- Producing an audit trail of who changed what, and why, for example for a software release report, or for ISO 9000 documentation.
- Discovering how a particular piece of code became broken, and deducing which change broke it. The `get -m` command is also useful for this, see Options for `get`.
- Listing all changes made on Friday afternoons, as a preparation for extra checking.