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## SECTION=system_libraries

config FLEX
	tristate
	prompt "flex"
	help
	  A fast lexical analyzer generator

	  Flex is a tool for generating scanners: programs which
	  recognized lexical patterns in text. It reads the given
	  input files for a description of a scanner to generate. The
	  description is in the form of pairs of regular expressions
	  and C code, called rules. Flex generates as output a C
	  source file, lex.yy.c, which defines a routine yylex(). This
	  file is compiled and linked with the -lfl library to produce
	  an executable. When the executable is run, it analyzes its
	  input for occurrences of the regular expressions. Whenever
	  it finds one, it executes the corresponding C code.

	  The behaviour of Flex has undergone a major change since
	  version 2.5.4a. Flex scanners are now reentrant, and it is
	  now possible to have multiple scanners in the same program
	  with differing sets of defaults, and the scanners play nicer
	  with modern C and C++ compilers. The Flip side is that Flex
	  no longer conforms to the POSIX lex behaviour, and the
	  scanners require conforming implementations when flex is
	  used in ANSI C mode.

	  Homepage: http://flex.sf.net/