This file can be generated by add-on programs to tell PHost what friendly codes to consider "special". Those will then never match during combat, etc.
It must contain sequences of up to three non-whitespace characters, separated by any amount of whitespace. Whitespace can be at least the space character (ASCII 32), the tab (ASCII 9) and the newline (ASCII 10). If one definition is less than three characters long, it causes all friendly codes starting with that sequences to be considered special.
E.g., if XTRFCODE.TXT contains "lfm md X", it will define "lfm" special, all codes starting with "md" (mine drop), and all starting with "X" (inhibit Super Spy Deluxe). Note that PHost itself does *not* consider "md" and "X" special because they should match.
PHost 3.4 and later automatically include their own friendly codes in this file at host-side; earlier versions did not. When players request this file, their copy will always include the built-in special codes.
