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

   --hex  use hexadecimal numbers instead of octal in debug outputs


   -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

          info flex

   should give you access to the complete manual.


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