Add-on or external programs sometimes introduce new special friendly codes to implement new behavior. PHost's handling of special friendly codes with respect to matching (i.e., special friendly codes never match) is a simple and consistent rule for players to follow. PHost implements a mechanism that allows it to recognize an add-on's new friendly codes as being special for the purposes of matching.
The friendly codes are listed in a file xtrfcode.txt which must reside in the game or root directory. It contains a list of all the special codes. Hosts should update it according to the add-ons they use. Since version 3.4, PHost automatically updates the file to include the PHost special codes (before, it would include them only in copies sent to players).
The file consists of a list of tokens with up to three characters, separated by whitespace and/or newlines. A three-character token defines just that friendly code special, shorter tokens declare special everything that starts with these characters. Matching is case-sensitive.
For example, if the xtrfcode.txt file contains
BJG AJG RJG J
then friendly codes of BJG, AJG, RJG as well as any friendly code that begins with J are considered special and will never match another friendly code. The above example may be suitable for use with the "Jumpgate" add-on (although the J code is overly broad: only codes consisting of J followed by a number are considered special by "Jumpgate", but there's no shorter way to describe that exactly than listing them all).
Here is another example xtrfcode.txt file that may be used with the RacePlus add-on (a bit broader than needed, too):
HUD ! !! EGG BAC TCC STB MK GWG RDV BBT SFG
Finally, another example xtrfcode.txt file that may be used with the FHost add-on:
FA FB FP FT FG TA TB BSG C BS ASG RSG J BCT RCT FCT BSB RSB FSB SSC KSP KPL AFC ATC GS EXC BUM MTN
