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LEX(1)			    General Commands 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 expres-
       sions 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 ex-
       pression	that is	recognized.

       The following lex 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(' ');

       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  ana-
	      lyzer.

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

       -f     `Faster' compilation: don't bother to pack the resulting tables;
	      limited to small programs.

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

									LEX(1)

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO

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