This product includes software developed by the University of California, Berkeley and its contributors.
Copyright (c) 1990 The Regents of the University of California. All rights reserved.
This code is derived from software contributed to Berkeley by Vern Paxson.
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flex, with Examples
flex is a tool for generating scanners: programs which recognize
lexical patterns in text. flex reads the given input files (or
its standard input if no file names are given) for a description of the
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. Compile and link this file with the `-lfl' library to
produce an executable. When the executable runs, it analyzes its input
for occurrences of the regular expressions. Whenever it finds one, it
executes the corresponding C code.
Some simple examples follow, to give you the flavor of using
flex.