1 .TH LEX 1
2 .SH NAME
3 lex \- generator of lexical analysis programs
4 .SH SYNOPSIS
5 .B lex
6 [
7 .B -tvn9
8 ]
9 [
10 .I file ...
11 ]
12 .SH DESCRIPTION
13 .I Lex
14 generates programs to be used in simple lexical analysis of text.
15 The input
16 .I files
17 (standard input default)
18 contain regular expressions
19 to be searched for and actions written in C to be executed when
20 expressions are found.
21 .PP
22 A C source program,
23 .B lex.yy.c
24 is generated.
25 This program, when run, copies unrecognized portions of
26 the input to the output,
27 and executes the associated
28 C action for each regular expression that is recognized.
29 .PP
30 The options have the following meanings.
31 .TP
32 .B -t
33 Place the result on the standard output instead of in file
34 .BR lex.yy.c .
35 .TP
36 .B -v
37 Print a one-line summary of statistics of the generated analyzer.
38 .TP
39 .B -n
40 Opposite of
41 .BR -v ;
42 .B -n
43 is default.
44 .TP
45 .B -9
46 Adds code to be able to compile through the native C compilers.
47 .SH EXAMPLES
48 This program converts upper case to lower,
49 removes blanks at the end of lines,
50 and replaces multiple blanks by single blanks.
51 .PP
52 .EX
53 %%
54 [A-Z]	putchar(yytext[0]+\'a\'-\'A\');
55 [ ]+$
56 [ ]+	putchar(\' \');
57 .EE
58 .SH FILES
59 .TF /sys/lib/lex/ncform
60 .TP
61 .B lex.yy.c
62 output
63 .TP
64 .B /sys/lib/lex/ncform
65 template
66 .SH "SEE ALSO"
67 .IR yacc (1), 
68 .MR sed (1)
69 .br
70 M. E. Lesk and E. Schmidt,
71 `LEX\(emLexical Analyzer Generator', 
72 .I
73 Unix Research System Programmer's Manual,
74 Tenth Edition, Volume 2.
75 .SH SOURCE
76 .B \*9/src/cmd/lex
77 .SH BUGS
78 Cannot handle
79 .SM UTF.
80 .PP
81 The asteroid to kill this dinosaur is still in orbit.