The Private Character Editor isn't something I am familiar with either,
but it may/should be there in Win XP and later, typically at
c:\windows\system32\eudcedit.exe
Historically it appears to be associated with systems using East Asian
fonts. It's possible that more people have started noticing it because
its more prominently displayed on Windows 7 menus or some such (I have a
feeling that's the reason I came across it recently).
There is more info. on how Windows treats these characters in the MSD
library at:
http://msdn.microsoft.com/en-us/library/dd317802(VS.85).aspx
In essence, the PCE creates small files containing "separate" private
character files in e.g.
C:\Users\<username>\AppData\Local\Microsoft\Windows\EUDC\
These files are .tte files and .euf files. I don't know what the .euf
file is but the .tte is essentially a .ttf file /of some kind/. The PCE
also creates the registry entries that specify whether the characters
are "linked" to particular fonts or all fonts.
Then in Character map, if you link to a specific font such as Arial, you see
Arial (on my copy of Vista this is an OT font)
Arial (Private Characters) (appears as a TT font)
If you link the character to "all fonts", Character Map lists a new font
called "All Fonts (Private Characters)"
However, these fonts do not seem to appear everywhere where fonts are
listed - e.g., they do not appear in the font list in the Insert->Symbol
facility. Presumably that dialog box either does not look up the
necessary registry entries and use them, or does not use whatever APIs
make the whole thing transparent.
Peter Jamieson
http://tips.pjmsn.me.uk