flex - the fast lexical analyser generator


flex [OPTIONS] [FILE]...


Generates programs that perform pattern-matching on text.

Table Compression:

-Ca, --align
 trade off larger tables for better memory alignment
-Ce, --ecs construct equivalence classes
-Cf do not compress tables; use -f representation
-CF do not compress tables; use -F representation
-Cm, --meta-ecs
 construct meta-equivalence classes
-Cr, --read
 use read() instead of stdio for scanner input
-f, --full generate fast, large scanner. Same as -Cfr
-F, --fast use alternate table representation. Same as -CFr
-Cem default compression (same as --ecs --meta-ecs)


-d, --debug
 enable debug mode in scanner
-b, --backup
 write backing-up information to lex.backup
-p, --perf-report
 write performance report to stderr
-s, --nodefault
 suppress default rule to ECHO unmatched text
-T, --trace
 flex should run in trace mode
-w, --nowarn
 do not generate warnings
-v, --verbose
 write summary of scanner statistics to stdout


-o, --outfile=FILE
 specify output filename
-S, --skel=FILE
 specify skeleton file
-t, --stdout
 write scanner on stdout instead of lex.yy.c
 name of C++ class
 create a C header file in addition to the scanner
--tables-file[=FILE] write tables to FILE

Scanner behavior:

-7, --7bit generate 7-bit scanner
-8, --8bit generate 8-bit scanner
-B, --batch
 generate batch scanner (opposite of -I)
-i, --case-insensitive
 ignore case in patterns
-l, --lex-compat
 maximal compatibility with original lex
-X, --posix-compat
 maximal compatibility with POSIX lex
-I, --interactive
 generate interactive scanner (opposite of -B)
 track line count in yylineno

Generated code:

-+, --c++ generate C++ scanner class
 #define macro defn (default defn is ’1’)
-L, --noline
 suppress #line directives in scanner
-P, --prefix=STRING
 use STRING as prefix instead of "yy"
-R, --reentrant
 generate a reentrant C scanner
 scanner for bison pure parser.
 include yylloc support.
 initialize yyin/yyout to stdin/stdout
--noansi-definitions old-style function definitions
 empty parameter list in prototypes
 do not include <unistd.h>
 do not generate a particular FUNCTION


-c do-nothing POSIX option
-n do-nothing POSIX option
-h, --help produce this help message
-V, --version
 report flex version


The full documentation for flex is maintained as a Texinfo manual. If the info and flex programs are properly installed at your site, the command
info flex
should give you access to the complete manual.

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