[OpenSPARC-T2-DV] / tools / perl-5.8.0 / man / man3 / IO::Handle.3

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.\" ========================================================================
.\"
.IX Title "IO::Handle 3"
.TH IO::Handle 3 "2002-06-01" "perl v5.8.0" "Perl Programmers Reference Guide"
.SH "NAME"
IO::Handle \- supply object methods for I/O handles
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 1
\&    use IO::Handle;
.Ve
.PP
.Vb 5
\&    $io = new IO::Handle;
\&    if ($io->fdopen(fileno(STDIN),"r")) {
\&        print $io->getline;
\&        $io->close;
\&    }
.Ve
.PP
.Vb 4
\&    $io = new IO::Handle;
\&    if ($io->fdopen(fileno(STDOUT),"w")) {
\&        $io->print("Some text\en");
\&    }
.Ve
.PP
.Vb 2
\&    use IO::Handle '_IOLBF';
\&    $io->setvbuf($buffer_var, _IOLBF, 1024);
.Ve
.PP
.Vb 1
\&    undef $io;       # automatically closes the file if it's open
.Ve
.PP
.Vb 1
\&    autoflush STDOUT 1;
.Ve
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
\&\f(CW\*(C`IO::Handle\*(C'\fR is the base class for all other \s-1IO\s0 handle classes. It is
not intended that objects of \f(CW\*(C`IO::Handle\*(C'\fR would be created directly,
but instead \f(CW\*(C`IO::Handle\*(C'\fR is inherited from by several other classes
in the \s-1IO\s0 hierarchy.
.PP
If you are reading this documentation, looking for a replacement for
the \f(CW\*(C`FileHandle\*(C'\fR package, then I suggest you read the documentation
for \f(CW\*(C`IO::File\*(C'\fR too.
.SH "CONSTRUCTOR"
.IX Header "CONSTRUCTOR"
.IP "new ()" 4
.IX Item "new ()"
Creates a new \f(CW\*(C`IO::Handle\*(C'\fR object.
.IP "new_from_fd ( \s-1FD\s0, \s-1MODE\s0 )" 4
.IX Item "new_from_fd ( FD, MODE )"
Creates an \f(CW\*(C`IO::Handle\*(C'\fR like \f(CW\*(C`new\*(C'\fR does.
It requires two parameters, which are passed to the method \f(CW\*(C`fdopen\*(C'\fR;
if the fdopen fails, the object is destroyed. Otherwise, it is returned
to the caller.
.SH "METHODS"
.IX Header "METHODS"
See perlfunc for complete descriptions of each of the following
supported \f(CW\*(C`IO::Handle\*(C'\fR methods, which are just front ends for the
corresponding built-in functions:
.PP
.Vb 12
\&    $io->close
\&    $io->eof
\&    $io->fileno
\&    $io->format_write( [FORMAT_NAME] )
\&    $io->getc
\&    $io->read ( BUF, LEN, [OFFSET] )
\&    $io->print ( ARGS )
\&    $io->printf ( FMT, [ARGS] )
\&    $io->stat
\&    $io->sysread ( BUF, LEN, [OFFSET] )
\&    $io->syswrite ( BUF, [LEN, [OFFSET]] )
\&    $io->truncate ( LEN )
.Ve
.PP
See perlvar for complete descriptions of each of the following
supported \f(CW\*(C`IO::Handle\*(C'\fR methods.  All of them return the previous
value of the attribute and takes an optional single argument that when
given will set the value.  If no argument is given the previous value
is unchanged (except for \f(CW$io\fR\->autoflush will actually turn \s-1ON\s0
autoflush by default).
.PP
.Vb 7
\&    $io->autoflush ( [BOOL] )                         $|
\&    $io->format_page_number( [NUM] )                  $%
\&    $io->format_lines_per_page( [NUM] )               $=
\&    $io->format_lines_left( [NUM] )                   $-
\&    $io->format_name( [STR] )                         $~
\&    $io->format_top_name( [STR] )                     $^
\&    $io->input_line_number( [NUM])                    $.
.Ve
.PP
The following methods are not supported on a per-filehandle basis.
.PP
.Vb 4
\&    IO::Handle->format_line_break_characters( [STR] ) $:
\&    IO::Handle->format_formfeed( [STR])               $^L
\&    IO::Handle->output_field_separator( [STR] )       $,
\&    IO::Handle->output_record_separator( [STR] )      $\e
.Ve
.PP
.Vb 1
\&    IO::Handle->input_record_separator( [STR] )       $/
.Ve
.PP
Furthermore, for doing normal I/O you might need these:
.IP "$io\->fdopen ( \s-1FD\s0, \s-1MODE\s0 )" 4
.IX Item "$io->fdopen ( FD, MODE )"
\&\f(CW\*(C`fdopen\*(C'\fR is like an ordinary \f(CW\*(C`open\*(C'\fR except that its first parameter
is not a filename but rather a file handle name, an IO::Handle object,
or a file descriptor number.
.IP "$io\->opened" 4
.IX Item "$io->opened"
Returns true if the object is currently a valid file descriptor, false
otherwise.
.IP "$io\->getline" 4
.IX Item "$io->getline"
This works like <$io> described in \*(L"I/O Operators\*(R" in perlop
except that it's more readable and can be safely called in a
list context but still returns just one line.
.IP "$io\->getlines" 4
.IX Item "$io->getlines"
This works like <$io> when called in a list context to read all
the remaining lines in a file, except that it's more readable.
It will also \fIcroak()\fR if accidentally called in a scalar context.
.IP "$io\->ungetc ( \s-1ORD\s0 )" 4
.IX Item "$io->ungetc ( ORD )"
Pushes a character with the given ordinal value back onto the given
handle's input stream.  Only one character of pushback per handle is
guaranteed.
.IP "$io\->write ( \s-1BUF\s0, \s-1LEN\s0 [, \s-1OFFSET\s0 ] )" 4
.IX Item "$io->write ( BUF, LEN [, OFFSET ] )"
This \f(CW\*(C`write\*(C'\fR is like \f(CW\*(C`write\*(C'\fR found in C, that is it is the
opposite of read. The wrapper for the perl \f(CW\*(C`write\*(C'\fR function is
called \f(CW\*(C`format_write\*(C'\fR.
.IP "$io\->error" 4
.IX Item "$io->error"
Returns a true value if the given handle has experienced any errors
since it was opened or since the last call to \f(CW\*(C`clearerr\*(C'\fR, or if the
handle is invalid. It only returns false for a valid handle with no
outstanding errors.
.IP "$io\->clearerr" 4
.IX Item "$io->clearerr"
Clear the given handle's error indicator. Returns \-1 if the handle is
invalid, 0 otherwise.
.IP "$io\->sync" 4
.IX Item "$io->sync"
\&\f(CW\*(C`sync\*(C'\fR synchronizes a file's in-memory state  with  that  on the
physical medium. \f(CW\*(C`sync\*(C'\fR does not operate at the perlio api level, but
operates on the file descriptor (similar to sysread, sysseek and
systell). This means that any data held at the perlio api level will not
be synchronized. To synchronize data that is buffered at the perlio api
level you must use the flush method. \f(CW\*(C`sync\*(C'\fR is not implemented on all
platforms. Returns \*(L"0 but true\*(R" on success, \f(CW\*(C`undef\*(C'\fR on error, \f(CW\*(C`undef\*(C'\fR
for an invalid handle. See \fIfsync\fR\|(3c).
.IP "$io\->flush" 4
.IX Item "$io->flush"
\&\f(CW\*(C`flush\*(C'\fR causes perl to flush any buffered data at the perlio api level.
Any unread data in the buffer will be discarded, and any unwritten data
will be written to the underlying file descriptor. Returns \*(L"0 but true\*(R"
on success, \f(CW\*(C`undef\*(C'\fR on error.
.IP "$io\->printflush ( \s-1ARGS\s0 )" 4
.IX Item "$io->printflush ( ARGS )"
Turns on autoflush, print \s-1ARGS\s0 and then restores the autoflush status of the
\&\f(CW\*(C`IO::Handle\*(C'\fR object. Returns the return value from print.
.IP "$io\->blocking ( [ \s-1BOOL\s0 ] )" 4
.IX Item "$io->blocking ( [ BOOL ] )"
If called with an argument \f(CW\*(C`blocking\*(C'\fR will turn on non-blocking \s-1IO\s0 if
\&\f(CW\*(C`BOOL\*(C'\fR is false, and turn it off if \f(CW\*(C`BOOL\*(C'\fR is true.
.Sp
\&\f(CW\*(C`blocking\*(C'\fR will return the value of the previous setting, or the
current setting if \f(CW\*(C`BOOL\*(C'\fR is not given. 
.Sp
If an error occurs \f(CW\*(C`blocking\*(C'\fR will return undef and \f(CW$!\fR will be set.
.PP
If the C functions \fIsetbuf()\fR and/or \fIsetvbuf()\fR are available, then
\&\f(CW\*(C`IO::Handle::setbuf\*(C'\fR and \f(CW\*(C`IO::Handle::setvbuf\*(C'\fR set the buffering
policy for an IO::Handle.  The calling sequences for the Perl functions
are the same as their C counterparts\*(--including the constants \f(CW\*(C`_IOFBF\*(C'\fR,
\&\f(CW\*(C`_IOLBF\*(C'\fR, and \f(CW\*(C`_IONBF\*(C'\fR for \fIsetvbuf()\fR\-\-except that the buffer parameter
specifies a scalar variable to use as a buffer. You should only
change the buffer before any I/O, or immediately after calling flush.
.PP
\&\s-1WARNING:\s0 A variable used as a buffer by \f(CW\*(C`setbuf\*(C'\fR or \f(CW\*(C`setvbuf\*(C'\fR \fBmust not
be modified\fR in any way until the IO::Handle is closed or \f(CW\*(C`setbuf\*(C'\fR or
\&\f(CW\*(C`setvbuf\*(C'\fR is called again, or memory corruption may result! Remember that
the order of global destruction is undefined, so even if your buffer
variable remains in scope until program termination, it may be undefined
before the file IO::Handle is closed. Note that you need to import the
constants \f(CW\*(C`_IOFBF\*(C'\fR, \f(CW\*(C`_IOLBF\*(C'\fR, and \f(CW\*(C`_IONBF\*(C'\fR explicitly. Like C, setbuf
returns nothing. setvbuf returns \*(L"0 but true\*(R", on success, \f(CW\*(C`undef\*(C'\fR on
failure.
.PP
Lastly, there is a special method for working under \fB\-T\fR and setuid/gid
scripts:
.IP "$io\->untaint" 4
.IX Item "$io->untaint"
Marks the object as taint\-clean, and as such data read from it will also
be considered taint\-clean. Note that this is a very trusting action to
take, and appropriate consideration for the data source and potential
vulnerability should be kept in mind. Returns 0 on success, \-1 if setting
the taint-clean flag failed. (eg invalid handle)
.SH "NOTE"
.IX Header "NOTE"
An \f(CW\*(C`IO::Handle\*(C'\fR object is a reference to a symbol/GLOB reference (see
the \f(CW\*(C`Symbol\*(C'\fR package).  Some modules that
inherit from \f(CW\*(C`IO::Handle\*(C'\fR may want to keep object related variables
in the hash table part of the \s-1GLOB\s0. In an attempt to prevent modules
trampling on each other I propose the that any such module should prefix
its variables with its own name separated by _'s. For example the IO::Socket
module keeps a \f(CW\*(C`timeout\*(C'\fR variable in 'io_socket_timeout'.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
perlfunc, 
\&\*(L"I/O Operators\*(R" in perlop,
IO::File
.SH "BUGS"
.IX Header "BUGS"
Due to backwards compatibility, all filehandles resemble objects
of class \f(CW\*(C`IO::Handle\*(C'\fR, or actually classes derived from that class.
They actually aren't.  Which means you can't derive your own 
class from \f(CW\*(C`IO::Handle\*(C'\fR and inherit those methods.
.SH "HISTORY"
.IX Header "HISTORY"
Derived from FileHandle.pm by Graham Barr <\fIgbarr@pobox.com\fR>
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129	.\" ========================================================================
130	.\"
131	.IX Title "IO::Handle 3"
132	.TH IO::Handle 3 "2002-06-01" "perl v5.8.0" "Perl Programmers Reference Guide"
133	.SH "NAME"
134	IO::Handle \- supply object methods for I/O handles
135	.SH "SYNOPSIS"
136	.IX Header "SYNOPSIS"
137	.Vb 1
138	\& use IO::Handle;
139	.Ve
140	.PP
141	.Vb 5
142	\& $io = new IO::Handle;
143	\& if ($io->fdopen(fileno(STDIN),"r")) {
144	\& print $io->getline;
145	\& $io->close;
146	\& }
147	.Ve
148	.PP
149	.Vb 4
150	\& $io = new IO::Handle;
151	\& if ($io->fdopen(fileno(STDOUT),"w")) {
152	\& $io->print("Some text\en");
153	\& }
154	.Ve
155	.PP
156	.Vb 2
157	\& use IO::Handle '_IOLBF';
158	\& $io->setvbuf($buffer_var, _IOLBF, 1024);
159	.Ve
160	.PP
161	.Vb 1
162	\& undef $io; # automatically closes the file if it's open
163	.Ve
164	.PP
165	.Vb 1
166	\& autoflush STDOUT 1;
167	.Ve
168	.SH "DESCRIPTION"
169	.IX Header "DESCRIPTION"
170	\&\f(CW\(C`IO::Handle\(C'\fR is the base class for all other \s-1IO\s0 handle classes. It is
171	not intended that objects of \f(CW\(C`IO::Handle\(C'\fR would be created directly,
172	but instead \f(CW\(C`IO::Handle\(C'\fR is inherited from by several other classes
173	in the \s-1IO\s0 hierarchy.
174	.PP
175	If you are reading this documentation, looking for a replacement for
176	the \f(CW\(C`FileHandle\(C'\fR package, then I suggest you read the documentation
177	for \f(CW\(C`IO::File\(C'\fR too.
178	.SH "CONSTRUCTOR"
179	.IX Header "CONSTRUCTOR"
180	.IP "new ()" 4
181	.IX Item "new ()"
182	Creates a new \f(CW\(C`IO::Handle\(C'\fR object.
183	.IP "new_from_fd ( \s-1FD\s0, \s-1MODE\s0 )" 4
184	.IX Item "new_from_fd ( FD, MODE )"
185	Creates an \f(CW\(C`IO::Handle\(C'\fR like \f(CW\(C`new\(C'\fR does.
186	It requires two parameters, which are passed to the method \f(CW\(C`fdopen\(C'\fR;
187	if the fdopen fails, the object is destroyed. Otherwise, it is returned
188	to the caller.
189	.SH "METHODS"
190	.IX Header "METHODS"
191	See perlfunc for complete descriptions of each of the following
192	supported \f(CW\(C`IO::Handle\(C'\fR methods, which are just front ends for the
193	corresponding built-in functions:
194	.PP
195	.Vb 12
196	\& $io->close
197	\& $io->eof
198	\& $io->fileno
199	\& $io->format_write( [FORMAT_NAME] )
200	\& $io->getc
201	\& $io->read ( BUF, LEN, [OFFSET] )
202	\& $io->print ( ARGS )
203	\& $io->printf ( FMT, [ARGS] )
204	\& $io->stat
205	\& $io->sysread ( BUF, LEN, [OFFSET] )
206	\& $io->syswrite ( BUF, [LEN, [OFFSET]] )
207	\& $io->truncate ( LEN )
208	.Ve
209	.PP
210	See perlvar for complete descriptions of each of the following
211	supported \f(CW\(C`IO::Handle\(C'\fR methods. All of them return the previous
212	value of the attribute and takes an optional single argument that when
213	given will set the value. If no argument is given the previous value
214	is unchanged (except for \f(CW$io\fR\->autoflush will actually turn \s-1ON\s0
215	autoflush by default).
216	.PP
217	.Vb 7
218	\& $io->autoflush ( [BOOL] ) $\|
219	\& $io->format_page_number( [NUM] ) $%
220	\& $io->format_lines_per_page( [NUM] ) $=
221	\& $io->format_lines_left( [NUM] ) $-
222	\& $io->format_name( [STR] ) $~
223	\& $io->format_top_name( [STR] ) $^
224	\& $io->input_line_number( [NUM]) $.
225	.Ve
226	.PP
227	The following methods are not supported on a per-filehandle basis.
228	.PP
229	.Vb 4
230	\& IO::Handle->format_line_break_characters( [STR] ) $:
231	\& IO::Handle->format_formfeed( [STR]) $^L
232	\& IO::Handle->output_field_separator( [STR] ) $,
233	\& IO::Handle->output_record_separator( [STR] ) $\e
234	.Ve
235	.PP
236	.Vb 1
237	\& IO::Handle->input_record_separator( [STR] ) $/
238	.Ve
239	.PP
240	Furthermore, for doing normal I/O you might need these:
241	.IP "$io\->fdopen ( \s-1FD\s0, \s-1MODE\s0 )" 4
242	.IX Item "$io->fdopen ( FD, MODE )"
243	\&\f(CW\(C`fdopen\(C'\fR is like an ordinary \f(CW\(C`open\(C'\fR except that its first parameter
244	is not a filename but rather a file handle name, an IO::Handle object,
245	or a file descriptor number.
246	.IP "$io\->opened" 4
247	.IX Item "$io->opened"
248	Returns true if the object is currently a valid file descriptor, false
249	otherwise.
250	.IP "$io\->getline" 4
251	.IX Item "$io->getline"
252	This works like <$io> described in \(L"I/O Operators\(R" in perlop
253	except that it's more readable and can be safely called in a
254	list context but still returns just one line.
255	.IP "$io\->getlines" 4
256	.IX Item "$io->getlines"
257	This works like <$io> when called in a list context to read all
258	the remaining lines in a file, except that it's more readable.
259	It will also \fIcroak()\fR if accidentally called in a scalar context.
260	.IP "$io\->ungetc ( \s-1ORD\s0 )" 4
261	.IX Item "$io->ungetc ( ORD )"
262	Pushes a character with the given ordinal value back onto the given
263	handle's input stream. Only one character of pushback per handle is
264	guaranteed.
265	.IP "$io\->write ( \s-1BUF\s0, \s-1LEN\s0 [, \s-1OFFSET\s0 ] )" 4
266	.IX Item "$io->write ( BUF, LEN [, OFFSET ] )"
267	This \f(CW\(C`write\(C'\fR is like \f(CW\(C`write\(C'\fR found in C, that is it is the
268	opposite of read. The wrapper for the perl \f(CW\(C`write\(C'\fR function is
269	called \f(CW\(C`format_write\(C'\fR.
270	.IP "$io\->error" 4
271	.IX Item "$io->error"
272	Returns a true value if the given handle has experienced any errors
273	since it was opened or since the last call to \f(CW\(C`clearerr\(C'\fR, or if the
274	handle is invalid. It only returns false for a valid handle with no
275	outstanding errors.
276	.IP "$io\->clearerr" 4
277	.IX Item "$io->clearerr"
278	Clear the given handle's error indicator. Returns \-1 if the handle is
279	invalid, 0 otherwise.
280	.IP "$io\->sync" 4
281	.IX Item "$io->sync"
282	\&\f(CW\(C`sync\(C'\fR synchronizes a file's in-memory state with that on the
283	physical medium. \f(CW\(C`sync\(C'\fR does not operate at the perlio api level, but
284	operates on the file descriptor (similar to sysread, sysseek and
285	systell). This means that any data held at the perlio api level will not
286	be synchronized. To synchronize data that is buffered at the perlio api
287	level you must use the flush method. \f(CW\(C`sync\(C'\fR is not implemented on all
288	platforms. Returns \(L"0 but true\(R" on success, \f(CW\(C`undef\(C'\fR on error, \f(CW\(C`undef\(C'\fR
289	for an invalid handle. See \fIfsync\fR\\|(3c).
290	.IP "$io\->flush" 4
291	.IX Item "$io->flush"
292	\&\f(CW\(C`flush\(C'\fR causes perl to flush any buffered data at the perlio api level.
293	Any unread data in the buffer will be discarded, and any unwritten data
294	will be written to the underlying file descriptor. Returns \(L"0 but true\(R"
295	on success, \f(CW\(C`undef\(C'\fR on error.
296	.IP "$io\->printflush ( \s-1ARGS\s0 )" 4
297	.IX Item "$io->printflush ( ARGS )"
298	Turns on autoflush, print \s-1ARGS\s0 and then restores the autoflush status of the
299	\&\f(CW\(C`IO::Handle\(C'\fR object. Returns the return value from print.
300	.IP "$io\->blocking ( [ \s-1BOOL\s0 ] )" 4
301	.IX Item "$io->blocking ( [ BOOL ] )"
302	If called with an argument \f(CW\(C`blocking\(C'\fR will turn on non-blocking \s-1IO\s0 if
303	\&\f(CW\(C`BOOL\(C'\fR is false, and turn it off if \f(CW\(C`BOOL\(C'\fR is true.
304	.Sp
305	\&\f(CW\(C`blocking\(C'\fR will return the value of the previous setting, or the
306	current setting if \f(CW\(C`BOOL\(C'\fR is not given.
307	.Sp
308	If an error occurs \f(CW\(C`blocking\(C'\fR will return undef and \f(CW$!\fR will be set.
309	.PP
310	If the C functions \fIsetbuf()\fR and/or \fIsetvbuf()\fR are available, then
311	\&\f(CW\(C`IO::Handle::setbuf\(C'\fR and \f(CW\(C`IO::Handle::setvbuf\(C'\fR set the buffering
312	policy for an IO::Handle. The calling sequences for the Perl functions
313	are the same as their C counterparts\(--including the constants \f(CW\(C`_IOFBF\*(C'\fR,
314	\&\f(CW\(C`_IOLBF\(C'\fR, and \f(CW\(C`_IONBF\(C'\fR for \fIsetvbuf()\fR\-\-except that the buffer parameter
315	specifies a scalar variable to use as a buffer. You should only
316	change the buffer before any I/O, or immediately after calling flush.
317	.PP
318	\&\s-1WARNING:\s0 A variable used as a buffer by \f(CW\(C`setbuf\(C'\fR or \f(CW\(C`setvbuf\(C'\fR \fBmust not
319	be modified\fR in any way until the IO::Handle is closed or \f(CW\(C`setbuf\(C'\fR or
320	\&\f(CW\(C`setvbuf\(C'\fR is called again, or memory corruption may result! Remember that
321	the order of global destruction is undefined, so even if your buffer
322	variable remains in scope until program termination, it may be undefined
323	before the file IO::Handle is closed. Note that you need to import the
324	constants \f(CW\(C`_IOFBF\(C'\fR, \f(CW\(C`_IOLBF\(C'\fR, and \f(CW\(C`_IONBF\(C'\fR explicitly. Like C, setbuf
325	returns nothing. setvbuf returns \(L"0 but true\(R", on success, \f(CW\(C`undef\(C'\fR on
326	failure.
327	.PP
328	Lastly, there is a special method for working under \fB\-T\fR and setuid/gid
329	scripts:
330	.IP "$io\->untaint" 4
331	.IX Item "$io->untaint"
332	Marks the object as taint\-clean, and as such data read from it will also
333	be considered taint\-clean. Note that this is a very trusting action to
334	take, and appropriate consideration for the data source and potential
335	vulnerability should be kept in mind. Returns 0 on success, \-1 if setting
336	the taint-clean flag failed. (eg invalid handle)
337	.SH "NOTE"
338	.IX Header "NOTE"
339	An \f(CW\(C`IO::Handle\(C'\fR object is a reference to a symbol/GLOB reference (see
340	the \f(CW\(C`Symbol\(C'\fR package). Some modules that
341	inherit from \f(CW\(C`IO::Handle\(C'\fR may want to keep object related variables
342	in the hash table part of the \s-1GLOB\s0. In an attempt to prevent modules
343	trampling on each other I propose the that any such module should prefix
344	its variables with its own name separated by _'s. For example the IO::Socket
345	module keeps a \f(CW\(C`timeout\(C'\fR variable in 'io_socket_timeout'.
346	.SH "SEE ALSO"
347	.IX Header "SEE ALSO"
348	perlfunc,
349	\&\(L"I/O Operators\(R" in perlop,
350	IO::File
351	.SH "BUGS"
352	.IX Header "BUGS"
353	Due to backwards compatibility, all filehandles resemble objects
354	of class \f(CW\(C`IO::Handle\(C'\fR, or actually classes derived from that class.
355	They actually aren't. Which means you can't derive your own
356	class from \f(CW\(C`IO::Handle\(C'\fR and inherit those methods.
357	.SH "HISTORY"
358	.IX Header "HISTORY"
359	Derived from FileHandle.pm by Graham Barr <\fIgbarr@pobox.com\fR>