PREFIX files are used by TROFF to define standard macros and setup default configurations. All current prefix files define the tilde character to be equivalent to an escape. Standard macros (which take one or more string arguments) include: BLD TEXT IN BOLD TYPE FAINT TEXT IN FAINT TYPE UL TEXT UNDERLINED NORM NORMAL LOWER CASE CHARACTERS LINE LINE DRAWING CHARACTERS ALT2 ALTERNATE CHAR SET 2 ALT3 ALTERNATE CHAR SET 3 SUB SUBSCRIPT SUPER SUPERSCRIPT PAIR SUPER/SUBSCRIPT HEX FULL COMBINATION - NOT YET IMPLEMENTED Some stndard macros do not include arguments within the macro call. These include: SBLD Start Bold Text NV Start Normal Video/Text