It is often useful to transmit a GEDCOM document together with a set of external files. The FamilySearch GEDZip file format is provided for this purpose. A FamilySearch GEDZip file is a Zip archive, as defined by http://www.pkware.com/appnote and standardized by ISO/IEC 21320-1:2015.
Note — A few details about the zip archive format are useful to fully understand GEDCOM Package :
- An archive can contain one or more files.
- Files within an archive can be added, removed, or updated individually without needing to re-process the rest of the archive.
- Libraries such as libzip allow applications to operate directly on the
- zip archive as if it were a normal directory tree.
- What the zip specification calls a “file name” is actually a local path and may contain directories.
- Directory separators are / internally and are converted to the appropriate form by the zip processing tool during zipping and unzipping. Because of this, unzipping a GEDZip file in any local directory results in all GEDZip FILE (p.58) references working as-is for the resulting gedcom.ged without the need for any additional processing.
More instructions and recommendations can be found in the actual specification.