F* - Headers Describing The File

Header Key Description
FC File checksum
FD File date produced
FE File error message
FX File change (May have more than one)
FU File Units
FV File Versioning
FC

File checksum

The software that created this file may implement file tampering security or content validation

FC algorithmid,checksumvalue
algorithmid [REQUIRED]

The algorithm used. Its up to the software that produced this file to understand this value

checksumvalue [REQUIRED]

The value of the checksum produced by the algorithm.

Examples:

FC myco2545,940360363
FD

File date produced

The date and time the file was generated

FD date,time
date [REQUIRED]
Format as 'yyyy/MM/dd'

The date the file was generated

time [REQUIRED]
Format as 'HH:mm:ss.SSS'

The time the file was generated

Examples:

FD 2016/07/29,10:00:24.353
FE

File error message

If the system that attempted to produce this file was unable to complete normally, an error message may be inserted here. The existence of this record implies the file is missing data.

FE errormessage
errormessage [REQUIRED]

The error message

Examples:

FE Failed to produce a result due to missing information!
FX

File change

This records any material changes made to information in the file to explain its contents.

Note: A file may contain more than one FX record 
FX fxdate,fxactionid,fxuser,fxinfo
fxdate [REQUIRED]

The date and time of the change

fxactionid [REQUIRED]

An action identifer

fxuser [optional]

An identifier of the user or system that made the change

fxinfo [REQUIRED]

More information about the change made

FU

File Units

This describes the units used. It supports a combination of metric and U.S. customary units of measurement systems.

FU unit_tag1[,unit_tag2...]
unit_tag(x) [optional]

A list of unit tags.

This parameter may be repeated

A Value for this parameter must be one of the following:
Value Meaning
metric Set speed to kph, length long to km, length short to meter, mass to kg.
uscustomary Set speed to mph, length long to mi, length short to foot, mass to lb.
uk Set speed to mph, length long to mi, length short to meter, mass to kg.
kph speed: Set to kilometers per hour
mph speed: Set to miles per hour
mps speed: Set to meters per second
meter length short: Set to meter
metre length short: Set to meter
foot length short: Set to feet
ft length short: Set to feet
inch length short: Set to inch
km length long: Set to kilometers
mi length long: Set to miles
kg mass: Set to kilograms
lb mass: Set to pounds
mac12 mac addressing: Set to 12 digit hex
mac17 mac addressing: Set to 17 digit hex
maclong mac addressing: Set to a Long value
llh coordinates: Set to lat, lng, height
olc coordinates: Set to Open Location Code

Examples:

FU mph,meter,kg
FU metric
Shorthand to set units to 'kph,meter,kg' 
FU uscustomary
Shorthand to set units to 'mph,foot,lb'

Default Behavior:

If this record is not present in the file, the following record is implied

FU metric

FV

File Versioning

Describes what version of software was used to produce the data file

FV gcversion,producer,sourcefile1[,sourcefile2...]
gcversion [REQUIRED]

This should always be "1" while the file format is in version 1.

producer [REQUIRED]

Any short text identifying the system that produced the file. Data suppliers can use this to track versions of their software that created the data file. Must not begin with whitespace.

sourcefile(x) [optional]

This may be used if conversion was done from another source file. File names must not begin with whitespace.

This parameter may be repeated

Examples:

FV 1,ReportMaker 4.3.25
FV 1,My system V2.3,sourcefile1.dat,sourcefile2.dat
Two source files were used by 'My system V2.3' to produce this output
FN

File Tally Totals Namespace

Namespace for count records [RESERVED FOR FUTURE USE]