The input of (special) characters for folder and file names depends on the operating system of your 4ALLPORTAL server. Accordingly, a distinction needs to be made as to which character sets a Windows-server-based file system or a Linux-based file system supports and which characters are not allowed (reserved characters).


Recommended characters

When assigning file or folder names, please bear in mind that compatibility regarding special characters must also be ensured on your desktop computer. File names in a Linux-based 4ALLPORTAL may contain special characters that your Windows computer cannot read. During downloads, this incompatibility may cause defective files or file names that contain hieroglyph-type characters.


To ensure compatibility across operating systems, we recommend that only the following special characters be used in folder and file names:

  • -  (Minus)
  • _  (Underscore)
  • Space

Example:  The-Fox_jumps_over the lazy Dog.jpg


Behavior

When importing files involving unsupported character formats, such as Cyrillic characters, the system will default to replacing them with question marks in the file name as fallback behavior.


Example: "Sample_ Узнавайте.jpg" becomes " Sample_?????????.jpg"


Depending on the character format, it is possible that the system may not be able to process the files despite the fallback behavior. Please remove the unsupported characters from the file names manually before uploading the files in 4ALLPORTAL.


Character sets by operating system


Windows server*

(version acc. to system requirements)

  • Character set: Unicode, UTF-16

  • Character set - length - file system: path name + file name max. 260 characters**

  • Character set - length - database: path name max. 450 characters + file name max. 255 characters
  • Unallowed characters: 0x00-0x1F 0x7F " * / : < > ? \ |
  • Assignment of folder and file names without characters (zero) is not possible 


Linux-based server*

(e.g., CentOS, Debian; versions acc. to system requirements)

  • Character set: all 8-bit based
  • Character set - length - file system: file system specific, e.g., “Ext4” max. 4096 characters

  • Character set - length - database: path name max. 450 characters + file name max. 255 characters

  • Unallowed characters: /
  • Assignment of folder and file names without characters (zero) is not possible 



Further information is available in Wikipedia article “Filename”, section “Comparison of filename limitations”



* Source: Wikipedia - Filename

** Value conforms to the requirements relating to the applications used in 4ALLPORTAL, such as ImageMagick, etc., not the file system