What does the "yy" in lex.yy.c stand for?

Question

What does the "yy" in lex.yy.c stand for?

Answer 1

Lex was meant to be used in concert with Yacc. The history and details of this are detailed in Steven Johnson's paper Yacc: Yet Another Compiler Compiler. The Yacc parser uses only names beginning in "yy' - there's no apparent meaning discussed beyond simply desiring a namespace. The "yy" in lex.yy.c indicates that the lex output is intended for a yacc parser.