What characters should be restricted from a Unix file name?

Question

Consider a Save As dialog with a free text entry where the user enters a file name as free text, then clicks a Save button. The software t

Answer 1

Although the accepted answer might have truth I think there's a benefit to having some restrictions that could be potentially annoying for scripting or other stuff:

• forward slash (/)
• backslash (\)
• NULL (\0)
• tick (`)
• starts with a dash (-)
• star (*)
• pipes (|)
• semicolon (;)
• quotations (" or ')
• colon (:)

( - maybe space though I'm reluctant to add that.)

As you can see you might just be better off whitelisting as @Gavin suggests...