The "deconstruct" command:

Usage fossil deconstruct ?OPTIONS? DESTINATION

This command exports all artifacts of a given repository and
writes all artifacts to the file system. The DESTINATION directory
will be populated with subdirectories AA and files AA/BBBBBBBBB.., where
AABBBBBBBBB.. is the 40+ character artifact ID, AA the first 2 characters.
If -L|--prefixlength is given, the length (default 2) of the directory
prefix can be set to 0,1,..,9 characters.

  -R|--repository REPOSITORY  deconstruct given REPOSITORY
  -L|--prefixlength N         set the length of the names of the DESTINATION
                              subdirectories to N
  --private                   Include private artifacts.

See also: rebuild, reconstruct