lex.1 (1519B)
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.