Mediaflux has very few limitations on what constitutes a valid asset (file) or namespace (directory) name. The only reserved character in Mediaflux is the slash '/' character, as this is the path delimiter (the character that divides the path into its components).
Because it is possible to access your data in Mediaflux through many protocols such as HTTPS, /wiki/spaces/KB/pages/5474252, SMB, SFTP, etc. it is possible to create an asset through one protocol that has an invalid name when accessed through another protocol. In particular, NFS and SFTP allow almost all characters, whereas SMB has more restrictions (see the reserved characters for Windows, below). If Mediaflux contains an asset that is invalid though a particular protocol, then the asset won't be visible as a file when mounted through that protocol. For example, the file 'foo:bar' would be visible if you access your project through NFS or SFTP but not if you accessed it through SMB.
Many of the Mediflux clients go to considerable lengths to deal with this for you, for example, Mediaflux Data Mover will replace invalid characters with underscore '_' when downloading to Windows.
Path length restrictions
A file path is the full path with all directory names and the file name, e.g. 'C:\Program Files\FileZilla FTP Client\filezilla.exe'. Most operating systems have quite long limits on the total path length (at least 4096 characters). However, many Windows applications are limited to a MAX_PATH value of 260, but Windows file names can easily exceed this limit. From Windows 10, version 1607, a larger MAX_PATH can be set to allow much longer paths to be used.
Case-sensitive, case-preserving file systems
Some file systems are case sensitive (e.g. Linux ext4), meaning that two files that differ only by case are considered different files. For example, the following are different files:
hello Hello
Other file systems are case-preserving (e.g. Windows NTFS), meaning that two files that differ only by case are considered the same file. You can however change the capitalisation of the file and that will be retained. For example, the following are the same file:
hello hEllo
On macOS, it is possible to create an APFS formatted filesystem as either case-sensitive or case-preserving, with the default being case-preserving.
Reserved characters and words
On Windows, the following are reserved characters:
< (less than) > (greater than) : (colon) " (double quote) / (forward slash) \ (backslash) | (vertical bar or pipe) ? (question mark) * (asterisk)
In addition, it is generally invalid to end a directory or file name with a space ' ' or period '.' character.
Do not use the following reserved names for the name of a file:
CON, PRN, AUX, NUL, COM0, COM1, COM2, COM3, COM4, COM5, COM6, COM7, COM8, COM9, COM¹, COM², COM³, LPT0, LPT1, LPT2, LPT3, LPT4, LPT5, LPT6, LPT7, LPT8, LPT9, LPT¹, LPT², and LPT³
Also avoid these names followed immediately by an extension; for example, NUL.txt and NUL.tar.gz are both equivalent to NUL.
On Linux filesystems, generally the only reserved character is slash '/', the same as on Mediaflux.
On macOS, in addition to slash '/', the colon ':' character is considered invalid, though you can create files with a colon character in them at the command line, and the colon will appear as a slash '/' when viewed through the macOS Finder.
Additional restrictions
There are some other file names that may cause issues with certain software components within the Mediaflux stack. In particular, namespaces or assets that begin or end with a space can cause issues with some clients.
You can't make folders on the desktop that have "System Action" or "Device" references such as con, nul and prn. Solution is to use another name or use 0 instead of o,O for C0n.
Here are others :
CON, PRN, AUX, CLOCK$, NUL, COM1, COM2, COM3, COM4, COM5, COM6, COM7, COM8, COM9,
LPT1, LPT2, LPT3, LPT4, LPT5, LPT6, LPT7, LPT8, LPT9