Naming limitations

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The synchronization application allows you to synchronize files between computers running different operating systems.

Unfortunately, not all systems have the same rules for naming files, and file names that are allowed on one system may not be allowed on another.

So for example, a file created on MacOS will not be synchronized with a computer running MS/DOS if its name contains certain characters.

To try to clarify this, here are some tips on characters to avoid:
- Naming rules by operating system
- Restrictions on Windows

   File names, including extensions, should not be longer than 256 characters;
   Folder names must not be longer than 243 characters;
   Document paths (i.e. document name + names of all its ancestors) must not be longer than 32766 characters;
   Document names must not contain the following characters: <>:"/\|?* ;
   Folder names and file extensions must not end with the following characters: ., ;
The following names are reserved: CON, PRN, AUX, NUL, COM1, COM2, COM3, COM4, COM5, COM6, COM7, COM8, COM9, LPT1, LPT2, LPT3, LPT4, LPT5, LPT6, LPT7, LPT8, LPT9.

Restrictions on macOS

   document names, including extensions, must not be longer than 255 characters;
   document paths (i.e. document name + names of all its ancestors) must not be longer than 1023 characters;
   document names must not contain the following characters: /.

MacOS has a funny feature: some characters are forbidden in theory but allowed in practice. Thus the /. Normally it is forbidden, because it is the character that is used as a separator in file names.

In practice, the Finder allows the creation of files whose name contains a /, but saves them on the disk by replacing the / with :.

Thus, some applications will see the file name with a / and others with :. The Cozy application, on the other hand, sees :.

Restrictions on GNU/Linux

   document names, including extensions, must not be longer than 255 characters;
   document paths (i.e. document name + names of all its ancestors) must not be longer than 4095 characters;
   document names must not contain the following characters: /.