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Diff for /src/usr.bin/lex/flex.1 between version 1.20 and 1.21

version 1.20, 2005/02/08 09:12:16 version 1.21, 2007/05/30 05:52:33
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 .Op Fl S Ar skeleton  .Op Fl S Ar skeleton
 .Op Ar filename ...  .Op Ar filename ...
 .Sm on  .Sm on
 .Sh OVERVIEW  .Sh DESCRIPTION
 This manual describes  .Nm
 .Nm ,  is a tool for generating
 a tool for generating programs that perform pattern-matching on text.  .Em scanners :
   programs which recognize lexical patterns in text.
   .Nm
   reads the given input files, or its standard input if no file names are given,
   for a description of a scanner to generate.
   The description is in the form of pairs of regular expressions and C code,
   called
   .Em rules .
   .Nm
   generates as output a C source file,
   .Pa lex.yy.c ,
   which defines a routine
   .Fn yylex .
   This file is compiled and linked with the
   .Fl 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.
   .Pp
 The manual includes both tutorial and reference sections:  The manual includes both tutorial and reference sections:
 .Bl -ohang  .Bl -ohang
 .It Sy Description  
 A brief overview of the tool.  
 .It Sy Some Simple Examples  .It Sy Some Simple Examples
 .It Sy Format of the Input File  .It Sy Format of the Input File
 .It Sy Patterns  .It Sy Patterns
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 Known problems with  Known problems with
 .Nm .  .Nm .
 .El  .El
 .Sh DESCRIPTION  
 .Nm  
 is a tool for generating  
 .Em scanners :  
 programs which recognize lexical patterns in text.  
 .Nm  
 reads the given input files, or its standard input if no file names are given,  
 for a description of a scanner to generate.  
 The description is in the form of pairs of regular expressions and C code,  
 called  
 .Em rules .  
 .Nm  
 generates as output a C source file,  
 .Pa lex.yy.c ,  
 which defines a routine  
 .Fn yylex .  
 This file is compiled and linked with the  
 .Fl 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.  
 .Sh SOME SIMPLE EXAMPLES  .Sh SOME SIMPLE EXAMPLES
 First some simple examples to get the flavor of how one uses  First some simple examples to get the flavor of how one uses
 .Nm .  .Nm .
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