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EFAX(1)								       EFAX(1)

       efax - send/receive faxes with Class 1, 2 or 2.0	fax modem

			(Please	read the fax man page first.)

       efax [ options ]	[ -t num [ file... ] ]

       Where options are:

       -a cmd	use  the  command ATcmd	when answering the phone.  The default
		is "A".

       -c caps	set the	local modem capabilities.  See the section on capabil-
		ities  below  for the format and meaning of caps.  For Class 1
		the default is 1,n,0,2,0,0,0,0 where n is  the	highest	 speed
		supported by the modem.	 For Class 2 the default is determined
		by the modem.

       -d dev	use the	fax modem connected to device  dev.   The  default  is

       -e cmd	if  a  CONNECT	response  indicates  a	voice  call, the shell
		/bin/sh	is exec(2)'ed with cmd as its command.

       -f fnt	use font file fnt for generating the header.  The default is a
		built-in  8x16	font.	See the	efix(1)	-f option for the font
		file format.

       -g cmd	if a CONNECT (or DATA) response	indicates  a  data  call,  the
		shell /bin/sh is exec(2)'ed with cmd as	its command.  cmd is a
		printf(3) format that may contain up to	6 %d escapes which are
		replaced  by  the  baud	rate following the most	recent CONNECT
		message. cmd typically exec's getty(8).

       -h hdr	put string `hdr' at the	top of each page.   The	 first	%d  in
		`hdr'  is  replaced by the page	number and the second, if any,
		is replaced by the number of pages being sent.

       -i str

       -j str

       -k str	send the command ATstr to the modem to initialize it.  -i com-
		mands  are sent	before the modem is put	into fax mode, -j com-
		mands after the	modem is in fax	mode, and -k commands just be-
		fore  efax exits.  The only default is a hang-up (ATH) command
		that is	sent before exiting only if no other  -k  options  are
		given.	Multiple options may be	used.

       -l id	set  the  local	identification string to id.  id should	be the
		local telephone	number in international	 format	 (for  example
		"+1 800	555 1212").  This is passed to the remote fax machine.
		Some fax machines may not accept characters  other  than  num-
		bers, space, and '+'.

       -n	force  line  buffering	of  stdout instead of block buffering.
		This might be necessary	if outputting UTF-8 to a terminal with
		translated  text  via NLS, since otherwise the terminal	may be
		confronted (when the buffer is flushed when full) with only  a
		partially  formed  UTF-8 character.  Don't use this option un-
		less you have to.

       -o opt	use option opt to accommodate a	non-standard fax modem	proto-
		col.   See  the	 MODEM REQUIREMENTS section below for more de-
		tails.	The options are:

	   0	Force use of Class 2.0 fax modem  commands.   The  modem  must
		support	Class 2.0.

	   2	Force  use of Class 2 fax modem	commands.  The modem must sup-
		port Class 2.

	   1	Force use of Class 1 fax modem commands. The modem  must  sup-
		port  Class 1.	By default efax	queries	the modem and uses the
		first of the three above classes which is supported by the mo-

	   a	use  software adaptive answer method.  If the first attempt to
		answer the call	does not result	in a data connection within  8
		seconds	the phone is hung up temporarily and answered again in
		fax mode (see "Accepting both fax and data calls" below).

	   e	ignore errors in modem initialization commands.

	   f	use "virtual flow control".  efax tries	to estimate the	number
		of  bytes  in the modem's transmit buffer and pauses as	neces-
		sary to	avoid filling it.  The modem's buffer  is  assumed  to
		hold  at  least	96 bytes.  This	feature	does not work properly
		with Class 2 modems that add redundant padding to scan	lines.
		Use  this  option  only	 if you	have problems configuring flow

	   h	use hardware (RTS/CTS) in addition to software (XON/XOFF) flow
		control.   Many	 modems	will stop responding if	this option is
		used.  See the section `Resolving Problems' before using  this

	   l	halve  the  time  between  testing lock	files when waiting for
		other programs to complete.  By	default	this is	8 seconds. For
		example	-olll sets the interval	to 1 second.

	   n	ignore requests	for pages to be	retransmitted. Use this	option
		if you don't care about	the quality of the received fax	or  if
		the  receiving	machine	is too fussy.  Otherwise each page may
		be retransmitted up to 3 times.

	   r	do not reverse bit order during	data  reception	 for  Class  2
		modems.	  Only	Multitech modems require this option. Not nor-
		mally required since efax detects these	modems.

	   x	send XON (DC1) instead of DC2 to start	data  reception.   Ap-
		plies to a very	few Class 2 modems only.

	   z	delay  an  additional  100 milliseconds	before each modem ini-
		tialization or reset command.  The initial delay  is  100  ms.
		For  example,  -ozzz produces a	400 ms delay.  Use with	modems
		that get confused when commands	arrive too quickly.

       -q n	ask for	retransmission of pages	received with more than	n  er-
		rors.  Default is 10.

       -r pat	each received fax page is stored in a separate file.  The file
		name is	created	using pat as a strftime(3) format  string.   A
		page  number  of  the form .001, .002, ...  is appended	to the
		file name.  If pat is blank ("") or no -r option  is  given  a
		default	string of "%m%d%H%M%S" is used.

       -s	remove lock file(s) after initializing the modem.  This	allows
		outgoing calls to proceed when efax is waiting for an incoming
		call.	If  efax detects modem activity	it will	attempt	to re-
		lock the device.  If the modem has been	locked	by  the	 other
		program	 efax  will  exit and return 1 (``busy'').  Normally a
		new efax process is then started  by  init(8).	The  new  efax
		process	 will then check periodically until the	lock file dis-
		appears	and then re-initialize the modem.

       -t num [file...]
		dial telephone	number	num  and  send	the  fax  image	 files
		file....   If used, this must be the last argument on the com-
		mand line.  The	telephone number num is	a string that may con-
		tain  any  dial	 modifiers that	the modem supports such	as a T
		prefix for tone	dialing	or commas  for	delays.	  If  no  file
		names  are  given the remote fax machine will be polled. If no
		-t argument is given efax will answer the phone	and attempt to
		receive	a fax.

       -u	use  UTF-8  and	not locale codeset (if different) for messages
		to stderr and stdout (see also the -n option) -	this is	useful
		if  efax is used with a	front-end which	expects	UTF-8 encoding
		of internationalized strings.

       -v strng	select types of	messages to be printed.	 Each lower-case  let-
		ter in strng enables one type of message:

		   e - errors
		   w - warnings
		   i - session progress	information
		   n - capability negotiation information
		   c - modem (AT) commands and responses
		   h - HDLC frame data (Class 1	only)
		   m - modem output
		   a - program arguments
		   r - reception error details
		   t - transmission details
		   f - image file details
		   x - lock file processing

		Up  to	two -v options may be used.  The first is for messages
		printed	to the standard	error and the second is	 for  messages
		to  the	standard output. The default is	"ewin" to the standard
		error only.

       -w	wait for an OK or CONNECT prompt instead of issuing an	answer
		(ATA)  command to receive a fax.  Use this option when the mo-
		dem is set to auto-answer (using S0=n) or if  another  program
		has already answered the call.

       -x lkf	use a UUCP-style lock file lkf to lock the modem device	before
		opening	it.  If	the device is locked,  efax  checks  every  15
		seconds	 until it is free.  Up to 16 -x	options	may be used if
		there are several names	for the	same device.  A	`#' prefix  on
		the  file  name	creates	an binary rather than text (HDB-style)
		lock file.  This is the	reverse	of what	was used  by  previous
		efax versions.

       efax  can  read	the same types of files	as efix(1) including text, T.4
       (Group 3), PBM, single- and  multi-page	TIFF  (G3  and	uncompressed).
       efax automatically determines the type of file from its contents.  TIFF
       files are recommended as	they contain information about the image  size
       and resolution.

       Each page to be sent should be converted	to a separate TIFF format file
       with Group 3 (G3) compression.  Received	files are also stored in  this
       format.	 The  EXAMPLES section below shows how efix and	other programs
       can be used to create, view and print these files.

       The operating system must provide short response	times to avoid	proto-
       col timeouts.  For Class	2 and 2.0 modems the delay should not exceed 1
       or 2 seconds.

       When using Class	1 modems the program must respond  to  certain	events
       within  55  milliseconds.   Longer delays may cause the fax protocol to
       fail in certain places (between DCS and TCF or between  RTC  and	 MPS).
       Class  1	 modems	 should	 therefore  not	be used	on systems that	cannot
       guarantee that the program will respond to incoming data	in  less  than
       55 milliseconds.	 In particular,	some intelligent serial	cards and ter-
       minal servers may introduce enough delay	to cause problems with Class 1

       The  operating  system must also	provide	sufficient low-level buffering
       to allow	uninterrupted transfer of data between the modem  and  a  disk
       file at the selected baud rate, typically 9600 bps.  Since the fax pro-
       tocol does not provide end-to-end flow  control	the  effectiveness  of
       flow control while receiving is limited by the size of the modem's buf-
       fer. This can be	less than 100 bytes.  Efax does	not use	 flow  control
       during reception.

       The  "Group"  is	 the protocol used to send faxes between fax machines.
       Efax supports the Group 3 protocol used over the	public telephone  net-

       The  "Class"  is	 the protocol used by computers	to control fax modems.
       Efax supports Class 1, 2	and 2.0	fax modems.

       Most fax	modems use XON/XOFF flow control when in fax mode.  This  type
       of flow control adds very little	overhead for fax use. Many modems have
       unreliable hardware (RTS/CTS) flow control in  fax  mode.   By  default
       efax enables only XON/XOFF flow control and the -oh option must be used
       to add hardware flow control.

       While some modems have serial buffers of	about 1k bytes,	many  inexpen-
       sive  modems  have buffers of about one hundred bytes and are thus more
       likely to suffer	overruns when sending faxes.

       A few older modems may need a delay between commands of more  than  the
       default	value  used  by	 efax (100 milliseconds).  If the delay	is too
       short, commands may not echo properly, may time out, or may give	incon-
       sistent	responses.   Use one or	more -oz options to increase the delay
       between modem initialization commands and use the E0 modem  initializa-
       tion command to disable echoing of modem	commands.

       By  default  efax  sends	DC2 to start the data flow from	the modem when
       receiving faxes from Class 2 modems.  A few older  modems  require  XON
       instead.	  Use  of  DC2	would cause the	modem to give an error message
       and/or the program to time out.	The -ox	option should be used in  this

       A  few  older Class 2 modems (e.g. some Intel models) don't send	DC2 or
       XON to start the	data flow to the  modem	 when  sending	faxes.	 After
       waiting 2 seconds efax will print a warning and start sending anyways.

       A  very few Class 2 modems do not reverse the bit order (MSB to LSB) by
       default on receive.  This might cause errors when trying	to display  or
       print the received files.  The -or option can be	used in	this case.

       Some  inexpensive  "9600	 bps" fax modems only transmit at 9600 bps and
       reception is limited to 4800 bps.

       The following Class 1 modems have been reported to work with efax: AT&T
       DataPort,  Cardinal Digital Fax Modem (14400), Digicom Scout+, Motorola
       Lifestyle 28.8, Motorola	Power 28.8,  QuickComm	Spirit	II,  Smartlink
       9614AV-Modem,  Supra  Faxmodem  144LC,  USR  Courier V.32bis Terbo, USR
       Sportster (V.32 and V.34), Zoom AFC 2.400, Zoom VFX14.4V.

       The following Class 2 modems have been reported to work with efax: 14k4
       Amigo  Communion	 fax/modem, Adtech Micro Systems 14.4 Fax/modem, askey
       modem type 1414VQE, AT&T	DataPort, ATT/Paradyne,	AT&T Paradyne  PCMCIA,
       Boca  modem, BOCA M1440E, Crosslink 9614FH faxmodem, FuryCard DNE 5005,
       GVC 14.4k internal, Intel 14.4 fax modem, Megahertz  14.4,  ,  Microcom
       DeskPorte  FAST	ES  28.8,  Motorola  UDS FasTalk II, MultiTech 1432MU,
       Practical Peripherals PM14400FXMT, Supra	V32bis,	 Telebit  Worldblazer,
       TKR  DM-24VF+,  Twincom	144/DFi,  ViVa 14.4/Fax	modem, Vobis Fax-Modem
       (BZT-approved), Zoom VFX14.4V, ZyXEL U-1496E[+],	ZyXEL Elite 2864I.

       The required modem initialization commands are generated	by efax.   Ad-
       ditional	commands may be	supplied as command-line arguments.  The modem
       must be set up to issue verbose(text) result codes.  The	following com-
       mand  does this and is sent by efax before trying to initialize the mo-

       Q0V1	respond	to commands with verbose result	codes

       The following commands may be useful for	special	purposes:

       X3	don't wait for dial tone before	dialing.  This may be used  to
		send a fax when	the call has already been dialed manually.  In
		this case use an empty string ("") as the  first  argument  to
		the  -t	 command.  Use X4 (usual default) to enable all	result

       M2	leave the monitor speaker turned on for	the  duration  of  the
		call (use M0 to	leave it off).

       L0	turn monitor speaker volume to minimum (use L3 for maximum).

       E0	disable	echoing	of modem commands.  See	the Resolving Problems
		section	below.

       &D2	returns	the modem to command mode when DTR  is	dropped.   The
		program	drops DTR at the start and end of the call if it can't
		get a response to a modem command.  You	can use	&D3  to	 reset
		the modem when DTR is dropped.

       S7=120	wait up	to two minutes (120 seconds) for carrier.  This	may be
		useful if the answering	fax machine takes a long time to start
		the  handshaking  operation (e.g. a combined fax/answering ma-
		chine with a long announcement).

       The capabilities	of the local hardware and software can be set using  a
       string of 8 digits separated by commas:



       vr  (vertical resolution) =
		0 for 98 lines per inch
		1 for 196 lpi

       br  (bit	rate) =
		0 for 2400 bps
		1 for 4800
		2 for 7200
		3 for 9600
		4 for 12000 (V.17)
		5 for 14400 (V.17)

       wd  (width) =
		0 for 8.5" (21.5 cm) page width
		1 for 10" (25.5	cm)
		2 for 12" (30.3	cm)

       ln  (length) =
		0 for 11" (A4: 29.7 cm)	page length
		1 for 14" (B4: 36.4 cm)
		2 for unlimited	page length

       df  (data format) =
		0 for 1-D coding
		1 for 2-D coding (not supported)

       ec  (error correction) =
		0 for no error correction

       bf  (binary file) =
		0 for no binary	file transfer

       st  (minimum scan time) =
		0 for zero delay per line
		1 for 5	ms per line
		3 for 10 ms per	line
		5 for 20 ms per	line
		7 for 40 ms per	line

       When receiving a	fax the	vr, wd,	and ln fields of the capability	string
       should be set to	the maximum values that	 your  display	software  sup-
       ports.  The default is 196 lpi, standard	(8.5"/21.5cm) width and	unlim-
       ited length.

       When sending a fax efax will determine vr and ln	from  the  image  file
       and set wd to the default.

       If  the	receiving  fax machine does not	support	high resolution	(vr=1)
       mode, efax will reduce the resolution by	combining pairs	of scan	lines.
       If  the	receiving  fax machine does not	support	the image's width then
       efax will truncate or pad as required. Most fax machines	can receive ln
       up to 2.	 Few machines support values of	wd other than 0.

       efax  adds  blank  scan lines at	the top	of each	image when it is sent.
       This allows room	for the	page header but	increases the  length  of  the
       image (by default about 0.1" or 2.5mm of	blank space is added).

       The  header  placed  in this area typically includes the	date and time,
       identifies the, and shows the page number  and  total  pages.   Headers
       cannot be disabled but the header string	can be set to a	blank line.

       The  default font for generating	the headers is the built-in 8x16 pixel
       font scaled to 12x24 pixels (about 9 point size).

       Note that both efax and efix have -f options to specify the font.  efIx
       uses the	font to	generate text when doing text-to-fax conversions (dur-
       ing "fax	make") while efAx uses the font	to generate the	header (during
       "fax send").

       A  session log is written to the	standard error stream.	This log gives
       status and error	messages from the program as selected by  the  -v  op-
       tion. A time stamp showing the full time	or just	minutes	and seconds is
       printed before each message.  Times printed along with modem  responses
       also show milliseconds.

       The program returns an error code as follows:

       0	The fax	was successfully sent or received.

       1	The  dialed  number  was  busy or the modem device was in use.
		Try again later.

       2	Something failed (e.g. file not	found  or  disk	 full).	 Don't
		retry.	Check the session log for more details.

       3	Modem  protocol	 error.	  The  program did not receive the ex-
		pected response	from the modem.	 The modem may not  have  been
		properly initialized, the correct -o options were not used, or
		a bug report may be in order.  Check the session log for  more

       4	The  modem is not responding.  Operator	attention is required.
		Check that the modem is	turned on and connected	to the correct

       5	The program was	terminated by a	signal.

       Creating	fax (G3) files

       The  efix  program can be used to convert text files to TIFF-G3 format.
       For example, the	following command will convert the text	file letter to
       the files letter.001, letter.002, etc,:

	      efix -nletter.%03d letter

       Ghostscript's  tiffg3  driver  can generate fax files in	TIFF-G3	format
       from postscript files.  For example, the	command:

	       gs -q -sDEVICE=tiffg3 -dNOPAUSE \
		   -sOutputFile=letter.%03d </dev/null

       will convert the	Postscript file into high-resolution	(vr=1)
       G3 fax image files letter.001, letter.002, ...

       The  images  should  have margins of at least 1/2 inch (1 cm) since the
       fax standard only requires that fax machines print a central portion of
       the image 196.6mm (7.7 inches) wide by 281.5mm (11.1 inches) high.

       The  efix  program  can also insert bitmaps in images to	create letter-
       head, signatures, etc.

       Printing	fax files

       You can use the efix program to print faxes  on	Postscript  or	HP-PCL
       (LaserJet)  printers.   For example, to print the received fax file re-
       ply.001 on a Postscript printer use the command:

	      efix -ops	reply.001 | lpr

       Sending fax files

       The following command will dial the number 222-2222 using tone  dialing
       and  send  a  two-page  fax  from the TIFF-G3 files letter.001 and let-
       ter.002 using the fax modem connected to	device /dev/cua1.

	      efax -d /dev/cua1	\
		   -t T222-2222	letter.001 letter.002

       Manual answer

       You can use efax	to answer the phone immediately	and start  fax	recep-
       tion.   Use  this  mode	if you need to answer calls manually to	see if
       they are	fax or voice.

       For example, the	following command will make the	fax  modem  on	device
       /dev/ttyS1 answer the phone and attempt to receive a fax.  The received
       fax will	be stored in the files reply.001, reply.002, and so  on.   The
       modem  will  identify itself as "555 1212" and receive faxes at high or
       low resolution (vr=1), at up to 14.4 kbps (br=5).

	      efax -d /dev/ttyS1 -l "555 1212" \
		 -c 1,5	-r reply

       Automatic answer

       The -w option makes efax	wait for characters to become  available  from
       the  modem (indicating an incoming call)	before starting	fax reception.
       Use the -w option and a -iS0=n option  to  answer  the  phone  after  n
       rings.	The example below will make the	modem answer incoming calls in
       fax mode	on the fourth ring and save the	 received  faxes  using	 files
       names corresponding to the reception date and time.

	      efax -d /dev/ttyb	-w -iS0=4 2>&1 >> fax.log

       Sharing the modem with outgoing calls

       The  modem  device  can	be shared by programs that use the UUCP	device
       locking protocol.  This includes	pppd, chat, minicom,  kermit,  uucico,
       efax,  cu,  and many others others.  However, locking will only work if
       all programs use	the same lock file.

       efax will lock the modem	device before opening it if one	or  more  UUCP
       lock  file  names are given with	-x options.  Most programs place their
       lock files in the /usr/spool/uucp or /var/lock directories and use  the
       name where dev	is the name of the device file in the /dev di-
       rectory that is to be locked.

       If the -s (share) option	is used, the lock file is removed while	 wait-
       ing for incoming	calls so other programs	can use	the same device.

       If  efax	detects	another	program	using the modem	while it is waiting to
       receive a fax, efax exits with a	termination code of 1.	 A  subsequent
       efax  process  using  this  device will wait until the other program is
       finished	before re-initializing the modem and starting to wait for  in-
       coming calls again.

       Programs	 that try to lock the modem device by using device locking fa-
       cilities	other than UUCP	lock files not be able to use this arbitration
       mechanism  because  the	device will still be open to the efax process.
       In this case you	will need to kill the efax process (e.g.  "fax	stop")
       before starting the other program.

       When  efax is waiting for a fax it leaves the modem ready to receive in
       fax mode	but removes the	lock file.  When a slip	or PPP	program	 takes
       over  the  modem	 port by setting up its	own lock file efax cannot send
       any more	commands to the	modem -- not even to reset it.	Therefore  the
       other program has to set	the modem back to data mode when it starts up.
       To do this add a	modem reset command (send ATZ expect OK) to the	begin-
       ning of your slip or PPP	chat script.

       Accepting both fax and data calls

       Many  modems  have an adaptive data/fax answer mode that	can be enabled
       using the -j+FAE=1 (for Class 1)	or -jFAA=1 (for	Class 2[.0])  initial-
       ization	string.	  The  type  of	call (data or fax) can then be deduced
       from the	modem's	responses.

       Some modems have	limited	adaptive answer	features  (e.g.	 only  working
       properly	 at certain baud rates or only in Class	2) or none at all.  In
       this case use the initialization	string -i+FCLASS=0 to answer  in  data
       mode first and the -oa option to	then hang up and try again in fax mode
       if the first answer attempt was not successful.	This method only works
       if  your	 telephone system waits	a few seconds after you	hang up	before
       disconnecting incoming calls.

       If the -g option	is used	then the option's argument will	be  run	 as  a
       shell  command  when an incoming	data call is detected.	Typically this
       command will exec getty(8).  This program should	expect to find the mo-
       dem  already  off-hook  and a lock file present so it should not	try to
       hang up the line	or create a lock file.	Note that the modem should  be
       set  up	to  report  the	 DCE-DTE  (modem-computer, e.g.	CONNECT	38400)
       speed, not the DCE-DCE (modem-modem, e.g. CONNECT  14400)  speed.   For
       many modems the initialization option -iW0 will set this.

       The following command will make efax answer incoming calls on /dev/cua1
       on the second ring.  This device	will be	 locked	 using	two  different
       lock  files  but	these lock files will be removed while waiting for in-
       coming calls (-s).  If a	data call is detected, the getty program  will
       be  run to initialize the terminal driver and start a login(1) process.
       Received	fax files will be stored using names like  Dec02-,
       in  the	/usr/spool/fax/incoming	directory and the log file will	be ap-
       pended to /usr/spool/fax/faxlog.cua1.

	      efax -d /dev/cua1	 -j '+FAA=1' \
		 -x /usr/spool/uucp/LCK..cua1 \
		 -x /usr/spool/uucp/LCK..ttyS1 \
		 -g "exec /sbin/getty -h /dev/cua1 %d" \
		 -iS0=2	-w -s \
		 -r "/usr/spool/fax/incoming/%b%d-%H.%I.%S" \
		 >> /usr/spool/fax/faxlog.cua1 2>&1

       Note that adaptive answer of either type	will not work for all callers.
       For some	data calls the duration	of the initial data-mode answer	may be
       too short for data handshaking to complete.  In other cases this	 dura-
       tion  may  be so	long that incoming fax calls will time out before efax
       switches	to fax mode.  In addition, some	 calling  fax  modems  mistake
       data-mode  answering tones for fax signaling tones and initiate fax ne-
       gotiation too soon.  If you use software	adaptive answer	you can	reduce
       the  value  of the initial data-mode answer (set	by TO_DATAF in efax.c)
       to get more reliable fax	handshaking or increase	it for	more  reliable
       data  handshaking.   However,  if  you need to provide reliable fax and
       data service to all callers you should use separate phone  numbers  for
       the two types of	calls.

       When a call is answered the modem goes on-line with the computer-to-mo-
       dem baud	rate fixed at the speed	used for the most recent  AT  command.
       When efax is waiting for	a fax or data call it sets the interface speed
       to 19200	bps since this is the speed required for fax operation.	  This
       prevents	full use of 28.8kbps modem capabilities.

       efax  can  answer  all incoming calls if	you place an entry for efax in
       /etc/inittab (for SysV-like systems) or /etc/ttytab (for	BSD-like  sys-
       tems).  The init(8) process will	run a new copy of efax when the	system
       boots up	and whenever the previous efax process terminates.  The	 init-
       tab  or	ttytab entry should invoke efax	by running the fax script with
       an answer argument.

       For example, placing the	following line in  /etc/inittab	 (and  running
       "kill -1	1") will make init run the fax script with the argument	answer
       every time previous process terminates and init is in runlevel 4	or 5.

	      s1:45:respawn:/bin/sh /usr/bin/fax answer

       For BSD-like systems (e.g. SunOS), a line  such	as  the	 following  in
       /etc/ttytab will	have the same effect:

	      ttya "/usr/local/bin/fax answer" unknown on

       You  should protect the fax script and configuration files against tam-
       pering since init will execute them as a	privileged (root) process.  If
       you  will  be allowing data calls via getty and login you should	ensure
       that your system	is reasonably secure (e.g. that	all user id's have se-
       cure passwords).

       If efax exec()'s	getty properly but you get a garbled login prompt then
       there is	probably a baud	rate mismatch between the modem	and  the  com-
       puter.  First, check the	efax log file to make sure the modem's CONNECT
       response	reported the serial port speed (e.g. 19200), not the modem-mo-
       dem  speed (e.g.	14400).	 Next, check the getty options and/or configu-
       ration files (e.g. /etc/gettydefs) for that particular baud rate.  Then
       run getty manually with the same	arguments and verify the port settings
       using ``stty </dev/XXX''.  Note that you'll  probably  want  to	enable
       hardware	 flow control for data connections (-h for agetty, CRTSCTS for

       A few programs won't work properly when efax is set up to answer	 calls
       because	they  don't  create  lock files.  You can put the shell	script
       ``wrapper'' below around	such programs  to  make	 them  work  properly.
       Change BIN and LOCKF to suit.

	      if [ -f $LOCKF ]
		      echo lock	file $LOCKF exists
		      exit 1
		      printf "%10d0 $$ >$LOCKF
		      $BIN $*
		      rm $LOCKF

       The "fax	answer"	script described above can be configured to e-mail the
       fax files received by the previous fax answer process to	 a  "fax  man-
       ager"  who  can then forward the	fax to the correct recipient.  The re-
       ceived fax files	are send as MIME attachments, one file per page, using
       the ``base64'' text encoding and	the ``image/tiff'' file	format.

       To  view	 the fax images	directly from your e-mail reader you will have
       to configure it with an application that	can display files of type  im-
       age/tiff.   Typically this is specified in a ``mailcap''	file.  For ex-
       ample, placing the following line in /etc/mailcap will  cause  the  fax
       file attachments	to be displayed	using the ``fax	view'' command.

       image/tiff; fax view %s

       You  can	configure a "fax" printer into the lpr print spooler that will
       fax a document out using	efax instead of	printing it.   This  allows  a
       network	server running efax to send faxes on behalf of other machines,
       including non-Unix clients.  In the following steps use the directories
       specified  in  the  fax	script if they are different than /usr/bin and
       /var/spool/fax (FAXDIR).	 To set	up a fax printer do the	 following  as

       (1) Create a link to the	fax script called ``faxlpr'' so	the fax	script
       can determine when it is	being invoked from the print spooler:

       ln -s /usr/bin/fax /usr/bin/faxlpr

       (2) Edit	/etc/printcap and add an entry such as:


       to define a printer called "fax".  Print	files will be spooled  to  the
       /var/spool/fax  (sd=)  directory	 and then piped	to the /usr/bin/faxlpr
       filter (if=).  Error messages will appear on /dev/console.

       (3) Create and/or set the permissions to	allow anyone to	read and write
       in the fax spool	directory.  For	example:

	      mkdir /var/spool/fax
	      chmod 777	/var/spool/fax

       (4) Create a printer daemon lock	file that is readable by anyone:

	      touch /var/spool/fax/lock
	      chmod 644	/var/spool/fax/lock

       You should now be able to send a	fax using the lpr interface by using a
       command such as:

	      lpr -P fax -J "555 1212"

       where the -J option is used to specify the phone	number or alias	to  be

       Note  that if more than one file	is given on the	command	line they will
       be concatenated before being passed to "fax send".  TIFF-G3, Postscript
       or  PBM	files  must therefore be sent one file at a time although TIFF
       and Postscript files may	contain	multiple pages.	  Only	multiple  text
       files  can  be  sent  in	one command.  Page breaks in text files	can be
       marked with form-feed characters.  Files	will be	converted and sent  at
       the default (high) resolution.

       You  can	 use lpq(1) to check the fax queue, lprm(1) to remove fax jobs
       and lpc(8) to control the spooler.  In each case	use the	 -Pfax	option
       to  specify  the	fax ``printer.'' A log file will be mailed to the user
       when the	fax is sent.

       You should also be able to send a fax from any networked	computer  that
       has  lpr-compatible remote printing software and	that allows you	to set
       the job name (-J	option)	to an  arbitrary  string.   Such  software  is
       available for most computers.

       See  the	 lpd(8)	and printcap(5)	man pages for information on the print
       spooler and for restricting access by host name (/etc/host.lpd)	or  by
       user group (the `rg' printcap entry).

       Double  check  the  configuration  setup	 in  the first part of the fax
       script, particularly the	modem device name and the lock file names.

       If  efax	 hangs	when  trying  to  open	the  modem  device  (typically
       /dev/ttyX),  the	 device	 is  either  already in	use by another process
       (e.g. pppd) or it requires the carrier detect line to be	true before it
       can  be	opened.	  Many systems define an alternate device name for the
       same physical device (typically cuaX) that can be opened	even  if  car-
       rier is not present or other programs are already using it.

       If  responses to	modem initialization commands are being	lost or	gener-
       ated at random, another processes (e.g. getty or	 an  efax  auto-answer
       process)	 may be	trying to use the modem	at the same time.  Try running
       efax while this other program is	running.   If  efax  does  not	report
       "/dev/ttyX locked or busy. waiting."  then the lock files names are not
       specified correctly.

       Attempt to send a fax. Check that the modem starts making  the  calling
       signal  (CNG,  a	 0.5 second beep every 3 seconds) as soon as it's fin-
       ished dialing.  This shows the modem is in fax mode.  You may  need  to
       set the SPKR variable to	-iM2L3 to monitor the phone line to do this.

       Listen for the answering	fax machine and	check that it sends the	answer
       signal (CED, a 3	 second	 beep)	followed  by  "warbling"  sounds  (DIS
       frames)	every  3  seconds.   If	 you hear a continuous sound (tones or
       noise) instead, then you've connected to	a data modem instead.

       Your modem should send back its own warble (DCS frame) in  response  to
       DIS immediately followed	by 1.5 seconds of noise	(a channel check).  If
       everything is OK, the receiving	end  will  send	 another  warble  (CFR
       frame) and your modem will start	to send	data.  If you have an external
       modem, check its	LEDs.  If flow control is working properly the modem's
       send  data  (SD)	 LED  will turn	off periodically while the fax data is

       Check the message showing the line count	and the	average	bit rate  when
       the  page transmission is done.	Low line counts	(under 1000 for	a let-
       ter size	image) or the warning "fax output buffer overflow" while send-
       ing  indicate  that  the	image data format is incorrect.	Check the file
       being sent using	the "fax view" command.

       If you get the error message ``flow control did not  work''  then  flow
       control was not active.	This usually results in	a garbled transmission
       and the receiving machine may reject the	page, abort the	call, print  a
       distorted or blank image	and/or hang up.

       The  warning "characters	received while sending"	or an <XOFF> character
       appearing after the transmission	means that the	operating  system  ig-
       nored the modem's XOFF flow control character.  Ensure that you are not
       running other programs such as getty or pppd at the same	time  as  efax
       since they will turn off	xon/xoff flow control.

       If  you	cannot get flow	control	to work	properly then enable ``virtual
       flow control'' with the -of option or hardware flow  control  with  the
       -oh option.

       Check  that  the	 remote	 machine confirms reception with a +FPTS:1 re-
       sponse (Class 2)	or an MCF frame	(Class 1).

       For Class 2 modems, the error message "abnormal call termination	 (code
       nn)" indicates that the modem detected an error and hung	up.

       Many  companies	advertise  services  that will fax back	information on
       their products.	These can be useful for	testing	fax reception.

       The message "run	length buffer overflow"	when  receiving	 indicates  an
       error  with  the	image data format.  You	may need to use	the -or	option
       with certain Class 2 modems.

       If efax displays	the message "can't happen (<details>)" please  send  a
       bug report to the author.

       Finally,	 don't	play  "option bingo," if you can't resolve the problem
       send a verbose log of the failed	session	(the output from fax  -v  ...)
       to the address below.

       A  Web Page with	pointers to the	latest version,	known bugs and patches
       is available at:

       For Linux Systems

       Independent packages provide  more  user-friendly  interfaces  to  efax
       (xfax,  tefax)  and provide an e-mail-to-fax (Qfax) gateway using efax.
       All  are	 available  by	 anonymous   FTP   from   in

       For Amiga Systems

       A port of an early version of efax for the Amiga	is available as	a com-
       ponent of a shareware voice mail	package, AVM, distributed by  Al  Vil-
       larica (

       Other Ports

       efax  is	 relatively  easy  to  port.   All system-dependent code is in
       efaxos.c.  An early version of efax was ported to  VMS.	 Version  0.8a
       was  ported  to	Win32  by  Luigi Capriotti.  Contact the author	if you
       would like to integrate the Win32 code into the current version.

       Efax was	written	by Ed Casas.  Please send comments or bug  reports  to

       Bug  reports should include the operating system, the type of the modem
       and a copy of a verbose session	log  that  demonstrates	 the  problem.
       It's  usually  impossible to help without a verbose log.	 Please	do not
       send fax	image files.

       efax is copyright 1993 -- 1999 Ed Casas.	 It may	be  used,  copied  and
       modified	under the terms	of the GNU Public License.

       Although	 efax  has been	tested it may have errors that will prevent it
       from working correctly on your system.  Some of these errors may	 cause
       serious	problems including loss	of data	and interruptions to telephone

       CCITT Recommendation T.30, "Procedures for Document Facsimile Transmis-
       sion in the General Switched Telephone Network".	1988

       CCITT Recommendation T.4, "Standardization of Group 3 Facsimile Appara-
       tus for Document	Transmission". 1988.

       For documentation on Class 1 and	Class 2	fax commands as	implemented by
       Connexant  (formerly Rockwell) modems see

       For the TIFF  specification  see
       vice/devrelations/PDFS/TN/TIFF6.pdf  or RFC 2301	(

       For information on Ghostscript see

       The pbm utilities can be	obtained by ftp	 from  in

       PCX and many other file formats are described in: Gunter	Born, The File
       Formats Handbook, International Thomson Computer	Press, 1995.

       The "Fax	Modem Source Book" by Andrew Margolis, published by John Wiley
       & Sons in 1994 (ISBN 0471950726), is a book on writing fax applications
       which includes source code.

       Dennis Bodson et. al., "FAX: Digital Facsimile Technology and  Applica-
       tions", Second Edition. Artech House, Boston. 1992.

       fax(1),	efix(1),  gs(1),  init(8), inittab(5), ttytab(5), printcap(5),
       lpd(8), printf(3), strftime(3).

       Can't read TIFF files with more than 1 strip

       Class 1 operation may fail if the program can't respond to certain data
       received	from the modem within 55 milliseconds.

       May fail	if multitasking	delays cause the received data to overflow the
       computer's serial device	buffer or if an	under-run of transmit data ex-
       ceeds 5 seconds.

       Polling does not	work.

       Does not	support	2-D coding, ECM, or BFT.

3rd Berkeley Distribution	  August 2007			       EFAX(1)


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