FLEX
Section: User Commands (1)
Updated: February 2008
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NAME
flex - the fast lexical analyser generator
 
SYNOPSIS
flex
[OPTIONS] [FILE]...
 
DESCRIPTION
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)
Debugging:
- -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
Files:
- -o, --outfile=FILE
- 
specify output filename
- -S, --skel=FILE
- 
specify skeleton file
- -t, --stdout
- 
write scanner on stdout instead of lex.yy.c
- --yyclass=NAME
- 
name of C++ class
- --header-file=FILE
- 
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)
- --yylineno
- 
track line count in yylineno
Generated code:
- -+,  --c++
- 
generate C++ scanner class
- -Dmacro[=defn]
- 
#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
- --bison-bridge
- 
scanner for bison pure parser.
- --bison-locations
- 
include yylloc support.
- --stdinit
- 
initialize yyin/yyout to stdin/stdout
- 
--noansi-definitions old-style function definitions
- --noansi-prototypes
- 
- empty parameter list in prototypes
- --nounistd
- 
do not include <unistd.h>
- --noFUNCTION
- 
do not generate a particular FUNCTION
Miscellaneous:
- -c
- 
do-nothing POSIX option
- -n
- 
do-nothing POSIX option
- 
-?
- -h, --help
- 
- produce this help message
- -V, --version
- 
report flex version
SEE ALSO
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.