title: Zettelstore boxes
role: manual
tags: #configuration #manual #zettelstore
syntax: zmk
back: 00001003300000 00001006020000 00001012054600 00001012080500
backward: 00001003300000 00001004010000 00001006020000 00001012054600 00001012080500
box-number: 1
copyright: (c) 2020-present by Detlef Stern <ds@zettelstore.de>
created: 20210126175322
forward: 00001004010000 00001004011400 00001004011600 00001004050000 00001005090000
lang: en
license: EUPL-1.2-or-later
modified: 20220307121547
published: 20220307121547
visibility: public

A Zettelstore must store its zettel somehow and somewhere.
In most cases you want to store your zettel as files in a directory.
Under certain circumstances you may want to store your zettel elsewhere.

An example are the [[predefined zettel|00001005090000]] that come with a Zettelstore.
They are stored within the software itself.
In another situation you may want to store your zettel volatile, e.g. if you want to provide a sandbox for experimenting.

To cope with these (and more) situations, you configure Zettelstore to use one or more __boxes__.
This is done via the ''box-uri-X'' keys of the [[startup configuration|00001004010000#box-uri-X]] (X is a number).
Boxes are specified using special [[URIs|https://en.wikipedia.org/wiki/Uniform_Resource_Identifier]], somehow similar to web addresses.

The following box URIs are supported:
; [!dir|''dir://DIR'']
: Specifies a directory where zettel files are stored.
''DIR'' is the file path.
Although it is possible to use relative file paths, such as ''./zettel'' (→ URI is ''dir://.zettel''), it is preferable to use absolute file paths, e.g. ''/home/user/zettel''.

  The directory must exist before starting the Zettelstore[^There is one exception: when Zettelstore is [[started without any parameter|00001004050000]], e.g. via double-clicking its icon, an directory called ''./zettel'' will be created.].

  It is possible to [[configure|00001004011400]] a directory box.
; [!file|''file:FILE.zip'' or ''file:///path/to/file.zip'']
: Specifies a ZIP file which contains files that store zettel.
You can create such a ZIP file, if you zip a directory full of zettel files.

  This box is always read-only.
; [!mem|''mem:'']
: Stores all its zettel in volatile memory.
If you stop the Zettelstore, all changes are lost.
To limit usage of volatile memory, you should [[configure|00001004011600]] this type of box, although the default values might be valid for your use case.
All boxes that you configure via the ''box-uri-X'' keys form a chain of boxes.
If a zettel should be retrieved, a search starts in the box specified with the ''box-uri-2'' key, then ''box-uri-3'' and so on.
If a zettel is created or changed, it is always stored in the box specified with the ''box-uri-1'' key.
This allows to overwrite zettel from other boxes, e.g. the predefined zettel.

If you use the ''mem:'' box, where zettel are stored in volatile memory, it makes only sense if you configure it as ''box-uri-1''.
Such a box will be empty when Zettelstore starts and only the first box will receive updates.
You must make sure that your computer has enough RAM to store all zettel.