diff options
author | Taru Karttunen <taruti@taruti.net> | 2011-03-30 16:49:47 +0300 |
---|---|---|
committer | Taru Karttunen <taruti@taruti.net> | 2011-03-30 16:49:47 +0300 |
commit | b41b9034225ab3e49980d9de55c141011b6383b0 (patch) | |
tree | 891014b4c2e803e01ac7a1fd2b60819fbc5a6e73 /sys/man/1/lex | |
parent | c558a99e0be506a9abdf677f0ca4490644e05fc1 (diff) |
Import sources from 2011-03-30 iso image - sys/man
Diffstat (limited to 'sys/man/1/lex')
-rwxr-xr-x | sys/man/1/lex | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/sys/man/1/lex b/sys/man/1/lex new file mode 100755 index 000000000..f0f148335 --- /dev/null +++ b/sys/man/1/lex @@ -0,0 +1,81 @@ +.TH LEX 1 +.SH NAME +lex \- generator of lexical analysis programs +.SH SYNOPSIS +.B lex +[ +.B -tvn9 +] +[ +.I file ... +] +.SH DESCRIPTION +.I Lex +generates programs to be used in simple lexical analysis of text. +The input +.I files +(standard input default) +contain regular expressions +to be searched for and actions written in C to be executed when +expressions are found. +.PP +A C source program, +.B lex.yy.c +is generated. +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. +.PP +The options have the following meanings. +.TP +.B -t +Place the result on the standard output instead of in file +.BR lex.yy.c . +.TP +.B -v +Print a one-line summary of statistics of the generated analyzer. +.TP +.B -n +Opposite of +.BR -v ; +.B -n +is default. +.TP +.B -9 +Adds code to be able to compile through the native C compilers. +.SH EXAMPLES +This program converts upper case to lower, +removes blanks at the end of lines, +and replaces multiple blanks by single blanks. +.PP +.EX +%% +[A-Z] putchar(yytext[0]+\'a\'-\'A\'); +[ ]+$ +[ ]+ putchar(\' \'); +.EE +.SH FILES +.TF /sys/lib/lex/ncform +.TP +.B lex.yy.c +output +.TP +.B /sys/lib/lex/ncform +template +.SH "SEE ALSO" +.IR yacc (1), +.IR sed (1) +.br +M. E. Lesk and E. Schmidt, +`LEX\(emLexical Analyzer Generator', +.I +Unix Research System Programmer's Manual, +Tenth Edition, Volume 2. +.SH SOURCE +.B /sys/src/cmd/lex +.SH BUGS +Cannot handle +.SM UTF. +.PP +The asteroid to kill this dinosaur is still in orbit. |