EventStore File Formats
From GlueXWiki
Key File Format
The Key File consists of a header and a series of records. The Key File stores indices into structured data files. Outside libraries are used to read the files. All information is stored in 32 bit unsigned words.
File header
The header contains identifying information and the number of records in the file.
| number of words | purpose of field |
|---|---|
| 1 | Format/Endian identifier: 2718281*256 + version number of file format |
| 1 | unique file identifier |
| 1 | number of events in file |
Record
A record consists of a run,event number pair that identifies the event, and its offset into the file.
| number of words | purpose of field |
|---|---|
| 1 | Run number |
| 1 | Event number |
| 1 | Index of event into data file |
