Re: Possible flex-2.5.4 bug

[Manoj Srivastava <srivasta@datasync.com>]

Hi,

	Each argument is scanned separately, with yy_scan_string. An
 end of file is generated, then, at the end of each string (each
 argument). There is no yywrap function defined.

 So, you call yylex thrice, on three separate, non-wrapped files. The
 second file (string, argument, whatever) does end inside a comment,
 and since there is no wrapping, the eof is final. The error is as
 you asked it to be reported.

	This does not seem to be a bug in flex.

	manoj

./a.out "foo<bleh>bar" "foo<bleh" "foo<bleh>bell"
 
 "foo<bleh"
 file ends inside a comment.

Excerpts from the documentation
======================================================================
File: flex.info,  Node: Multiple buffers,  Next: End-of-file rules,  Prev: Star\
t conditions,  Up: Top

Multiple input buffers
======================

 [...]

   Three routines are available for setting up input buffers for
scanning in-memory strings instead of files.  All of them create a new
input buffer for scanning the string, and return a corresponding
`YY_BUFFER_STATE' handle (which you should delete with
`yy_delete_buffer()' when done with it).  They also switch to the new
buffer using `yy_switch_to_buffer()', so the next call to `yylex()' will
start scanning the string.

`yy_scan_string(const char *str)'
     scans a NUL-terminated string.

`yy_scan_bytes(const char *bytes, int len)'
     scans `len' bytes (including possibly NUL's) starting at location
     BYTES.

   Note that both of these functions create and scan a *copy* of the
string or bytes.  (This may be desirable, since `yylex()' modifies the
contents of the buffer it is scanning.) 
----------------------------------------------------------------------
File: flex.info,  Node: Generated scanner,  Next: Start conditions,  Prev: Acti\
ons,  Up: Top

 [...]

   When the scanner receives an end-of-file indication from YY_INPUT,
it then checks the `yywrap()' function.  If `yywrap()' returns false
(zero), then it is assumed that the function has gone ahead and set up
`yyin' to point to another input file, and scanning continues.  If it
returns true (non-zero), then the scanner terminates, returning 0 to
its caller.  Note that in either case, the start condition remains
unchanged; it does *not* revert to `INITIAL'.

   If you do not supply your own version of `yywrap()', then you must
either use `%option noyywrap' (in which case the scanner behaves as
though `yywrap()' returned 1), or you must link with `-lfl' to obtain
the default version of the routine, which always returns 1.

-- 
 Ripping Yarns "Mind you, not as bad as the night Archie Pettigrew ate
 some sheep's testicles for a bet...God, that bloody sheep kicked
 him..."
Manoj Srivastava               <url:mailto:srivasta@acm.org>
Mobile, Alabama USA            <url:http://www.datasync.com/%7Esrivasta/>


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