# 2.11BSD#431 - /usr/man/cat1/lex.0

    LEX(1)		    UNIX Programmer's Manual		   LEX(1)

    NAME
         lex - generator of lexical analysis programs

    SYNOPSIS
         lex [ -tvfn ] [ file ] ...

    DESCRIPTION
         Lex generates programs to be used in simple lexical analyis
         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, to be compiled
         thus:

    	  cc lex.yy.c -ll

         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.

         -f   "Faster" compilation: don't bother to pack the result-
    	  ing tables; limited to small programs.

    EXAMPLE
    	  lex lexcommands

         would draw lex instructions from the file lexcommands, and
         place the output in lex.yy.c

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

         is an example of a lex program that would be put into a lex
         command file.  This program converts upper case to lower,
         removes blanks at the end of lines, and replaces multiple
         blanks by single blanks.

    Printed 11/26/99	 April 14, 1986                         1

    LEX(1)		    UNIX Programmer's Manual		   LEX(1)

    SEE ALSO
         yacc(1), sed(1)
         M. E. Lesk and E. Schmidt, LEX - Lexical Analyzer Generator

    Printed 11/26/99	 April 14, 1986                         2

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