plan9 man page for lex

LEX(1)							      General Commands Manual							    LEX(1)

NAME
       lex - generator of lexical analysis programs

SYNOPSIS
       lex [ -tvn ] [ file ...	]

DESCRIPTION
       Lex generates programs to be used in simple lexical analysis of text.  The input files (standard input default) contain regular expressions
       to be searched for and actions written in C to be executed when expressions are found.

       A C source program, lex.yy.c is generated.  This program, when run, copies unrecognized portions of the input to the output,  and  executes
       the associated C action for each regular expression that is recognized.

       The options have the following meanings.

       -t     Place the result on the standard output instead of in file lex.yy.c.

       -v     Print a one-line summary of statistics of the generated analyzer.

       -n     Opposite of -v; -n is default.

EXAMPLES
       This program converts upper case to lower, removes blanks at the end of lines, and replaces multiple blanks by single blanks.

       %%
       [A-Z]	 putchar(yytext[0]+'a'-'A');
       [ ]+$
       [ ]+ putchar(' ');

FILES
       lex.yy.c
	      output

       /sys/lib/lex/ncform
	      template

SEE ALSO
       yacc(1), sed(1)
       M. E. Lesk and E. Schmidt, `LEX--Lexical Analyzer Generator', Unix Research System Programmer's Manual, Tenth Edition, Volume 2.

SOURCE
       /sys/src/cmd/lex

BUGS
       Cannot handle UTF.
       The asteroid to kill this dinosaur is still in orbit.

																	    LEX(1)