File Naming Convention

2005-10-17

Description

CC

represents a two-character prefix for the file name (0-9, A-Z). Ideally, this will be a mnemonic code for the measurement, instrument, or subject of the file.

yyyy

represents four digits specifying year (i.e. 1997, 2001, etc.).

MM

represents two digits specifying month number (01-12).

dd

represents two digits specifying day number (01-31).

hh

represents an optional two digits which specify an hour (00-23).

mm

represents an optional two digits which specify minutes (00-59).

ss

represents an optional two digits which specify seconds (00-59).

c

represents an optional identifier for a particular type of file, where c can be one or more characters.

Ln

represents an aircraft launch counter. When the contents of a file pertain to a second or third aircraft launch on the indicated date then use Ln to indicate the launch number (i.e. L2, L3, etc.). If this parameter is omitted from the file name then launch number one is implied.

Vn

represents a volume counter for a multi-volume set of files. It is unlikely that this option will ever be used in the online archives, but its description is included, just in case it becomes useful.

1. For ASCII data files, the volume number (the n in Vn) must match the volume number (IVOL) in the sixth line of the file header.
2. The number of digits used in each volume number must be the same (V1, V2, V3, ..., or V01, V02, V03, ..., etc.).
3. If Vn is omitted from the file name then volume number one of a one-volume file set is implied (the default).

P

represents two or more characters to identify the measurement platform, source, or association of the data (for data files), or image file type (for image files).

1. Dates and times in file names are always UTC.
2. In general, the date and time in the file name give the date/time at which the data within the file begin (data files), or date/time at which the image applies (image files).
   • For aircraft data files, the date always refers to the UTC date of launch, and further specification of time in those file names is discouraged.
3. There can be two, four, or six digits following the first underscore, which represent hh, hhmm, or hhmmss.
4. If a file name does not include a time but does include other optional parameters then the first of those parameters is separated from the date by two underscores, e.g., CCyyyyMMdd__Ln.P.
5. File name codes are constructed from the constant parts of the file names and used as a shorthand way to reference a particular type of file. File name codes have one of the following forms (the date/time and Ln and Vn are variable parts of a file name):
   1. CC.P
   2. CC__c.P
6. For a particular archive account, each file name code must be unique, and therefore each file name will also be unique.
7. If two or more file codes use the same prefix CC and extension P then all of those codes must also include a c identifier, and each CC__c.P code must be unique.
   • Without this rule, an archive directory could include some AA.DC8 files and some AA__5HZ.DC8 files, and there would not be a simple way for users to list or download just the AA.DC8 files.
8. File catalogs (datatable.* and imagetable.*) are included in the docs directory of each archive account to link file name codes, and therefore file names, with the contents or subject of each type of file.

Examples