L.SYS(5)	    UNIX Programmer's Manual		 L.SYS(5)



NAME
     L.sys - UUCP remote host description file

DESCRIPTION
     The _L._s_y_s file is consulted by the UUCP daemon _u_u_c_i_c_o(8) for
     information on remote systems.  _L._s_y_s includes the system
     name, appropriate times to call, phone numbers, and a login
     and password for the remote system.  _L._s_y_s is thus a
     privileged file, owned by the UUCP Administrator; it is
     accessible only to the Administrator and to the superuser.

     Each line in _L._s_y_s describes one connection to one remote
     host, and has the form:

     System  Times  Caller  Class  Device/Phone_Number	[Expect  Send]....

     Fields can be separated by any number of blanks or tabs.
     Lines beginning with a `#' character are comments; long
     lines can be continued by appending a `\' character to the
     end of the line.

     The first five fields (_S_y_s_t_e_m through _D_e_v_i_c_e/_P_h_o_n_e__N_u_m_b_e_r)
     specify the hardware mechanism that is necessary to make a
     connection to a remote host, such as a modem or network.
     _U_u_c_i_c_o searches from the top down through _L._s_y_s to find the
     desired _S_y_s_t_e_m; it then opens the _L-_d_e_v_i_c_e_s(5) file and
     searches for the first available device with the same
     _C_a_l_l_e_r, _C_l_a_s_s, and (possibly) _D_e_v_i_c_e.  (``Available'' means
     that the device is ready and not being used for something
     else.) _U_u_c_i_c_o attempts a connection using that device; if
     the connection cannot be made (for example, a dialer gets a
     busy signal), _u_u_c_i_c_o tries the next available device. If
     this also fails, it returns to _L._s_y_s to look for another
     line for the same _S_y_s_t_e_m.	If none is found, _u_u_c_i_c_o gives
     up.

     _S_y_s_t_e_m is the hostname of the remote system.  Every machine
     with which this system communicates via UUCP should be
     listed, regardless of who calls whom.  Systems not listed in
     _L._s_y_s will not be permitted a connection.	The local host-
     name should not appear here for security reasons.

     _T_i_m_e_s is a comma-separated list of the times of the day and
     week that calls are permitted to this _S_y_s_t_e_m.  _T_i_m_e_s is most
     commonly used to restrict long distance telephone calls to
     those times when rates are lower.	List items are con-
     structed as:

	  _k_e_y_w_o_r_dhhmm-hhmm/_g_r_a_d_e;_r_e_t_r_y__t_i_m_e

     _K_e_y_w_o_r_d is required, and must be one of:




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L.SYS(5)	    UNIX Programmer's Manual		 L.SYS(5)



     Any     Any time, any day of the week.

     Wk      Any weekday. In addition, Mo, Tu, We, Th, Fr, Sa,
	     and Su can be used for Monday through Sunday,
	     respectively.

     Evening When evening telephone rates are in effect, from
	     1700 to 0800 Monday through Friday, and all day
	     Saturday and Sunday.  Evening is the same as
	     Wk1700-0800,Sa,Su.

     Night   When nighttime telephone rates are in effect, from
	     2300 to 0800 Monday through Friday, all day Satur-
	     day, and from 2300 to 1700 Sunday.  Night is the
	     same as Any2300-0800,Sa,Su0800-1700.

     NonPeak This is a slight modification of Evening.	It
	     matches when the USA X.25 carriers have their lower
	     rate period. This is 1800 to 0700 Monday through
	     Friday, and all day Saturday and Sunday.  NonPeak is
	     the same as Any1800-0700,Sa,Su.

     Never   Never call; calling into this _S_y_s_t_e_m is forbidden or
	     impossible.  This is intended for polled connec-
	     tions, where the remote system calls into the local
	     machine periodically.  This is necessary when one of
	     the machines is lacking either dial-in or dial-out
	     modems.

     The optional _h_h_m_m-_h_h_m_m subfield provides a time range that
     modifies the keyword.  _h_h_m_m refers to _h_o_u_r_s and _m_i_n_u_t_e_s in
     24-hour time (from 0000 to 2359).	The time range is permit-
     ted to "wrap" around midnight, and will behave in the obvi-
     ous way. It is invalid to follow the Evening, NonPeak, and
     Night keywords with a time range.

     The _g_r_a_d_e subfield is optional; if present, it is composed
     of a `/' (slash) and single character denoting the _g_r_a_d_e of
     the connection, from 0 to 9, A to Z, or a to z.  This speci-
     fies that only requests of grade _g_r_a_d_e or better will be
     transferred during this time.  (The grade of a request or
     job is specified when it is queued by _u_u_c_p or _u_u_x.) By con-
     vention, mail is sent at grade C, news is sent at grade d,
     and uucp copies are sent at grade n.  Unfortunately, some
     sites do not follow these conventions, so it is not 100%
     reliable.

     The _r_e_t_r_y__t_i_m_e subfield is optional; it must be preceded by
     a `;' (semicolon) and specifies the time, in minutes, before
     a failed connection may be tried again.  (This restriction
     is in addition to any constraints imposed by the rest of the
     _T_i_m_e field.) By default, the retry time starts at 10 minutes



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     and gradually increases at each failure, until after 26
     tries _u_u_c_i_c_o gives up completely (MAX RETRIES). If the retry
     time is too small, _u_u_c_i_c_o may run into MAX RETRIES too soon.

     _C_a_l_l_e_r is the type of device used:

     ACU     Automatic call unit or auto-dialing modem such as
	     the Hayes Smartmodem 1200 or Novation ``Smart Cat''.
	     See _L-_d_e_v_i_c_e_s for a list of supported modems.

     DIR     Direct connect; hardwired line (usually RS-232) to a
	     remote system.

     MICOM   Micom Terminal Switch.

     PAD     X.25 PAD connection.

     PCP     GTE Telenet PC Pursuit. See _L-_d_e_v_i_c_e_s for configura-
	     tion  details.

     SYTEK   Sytek high-speed dedicated modem port connection.

     TCP     Berkeley TCP/IP or 3Com UNET connection. These are
	     mutually exclusive.  TCP ports do not need entries
	     in _L-_d_e_v_i_c_e_s since all the necessary information is
	     contained in _L._s_y_s.  If several alternate ports or
	     network connections should be tried, use multiple
	     _L._s_y_s entries.

     _C_l_a_s_s is usually the speed (baud) of the device, typically
     300, 1200, or 2400 for ACU devices and 9600 for direct
     lines.  Valid values are device dependent, and are specified
     in the _L-_d_e_v_i_c_e_s file.

     On some devices, the baud may be preceded by a non-numeric
     prefix.  This is used in _L-_d_e_v_i_c_e_s to distinguish among dev-
     ices that have identical _C_a_l_l_e_r and baud, but yet are dis-
     tinctly different. For example, 1200 could refer to all Bell
     212-compatible modems, V1200 to Racal-Vadic modems, and
     C1200 to CCITT modems, all at 1200 baud.

     On TCP connections, _C_l_a_s_s is the port number (an integer
     number) or a port name from /_e_t_c/_s_e_r_v_i_c_e_s that is used to
     make the connection. For standard Berkeley TCP/IP, UUCP nor-
     mally uses port number 540.

     _D_e_v_i_c_e/_P_h_o_n_e__N_u_m_b_e_r varies based on the _C_a_l_l_e_r field.  For
     ACU devices, this is the phone number to dial.  The number
     may include: digits 0 through 9; # and * for dialing those
     symbols on tone telephone lines; - (hyphen) to pause for a
     moment, typically two to four seconds; = (equal sign) to
     wait for a second dial tone (implemented as a pause on many



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     modems). Other characters are modem dependent; generally
     standard telephone punctuation characters (such as the slash
     and parentheses) are ignored, although _u_u_c_i_c_o does not
     guarantee this.

     The phone number can be preceded by an alphabetic string;
     the string is indexed and converted through the
     _L-_d_i_a_l_c_o_d_e_s(5) file.

     For DIR devices, the _D_e_v_i_c_e/_P_h_o_n_e__N_u_m_b_e_r field contains the
     name of the device in /_d_e_v that is used to make the connec-
     tion. There must be a corresponding line in _L-_d_e_v_i_c_e_s with
     identical _C_a_l_l_e_r, _C_l_a_s_s, and _D_e_v_i_c_e fields.

     For TCP and other network devices, _D_e_v_i_c_e/_P_h_o_n_e__N_u_m_b_e_r holds
     the true network name of the remote system, which may be
     different from its UUCP name (although one would hope not).

     _E_x_p_e_c_t and _S_e_n_d refer to an arbitrarily long set of strings
     that alternately specify what to _e_x_p_e_c_t and what to _s_e_n_d to
     login to the remote system once a physical connection has
     been established.	A complete set of expect/send strings is
     referred to as an _e_x_p_e_c_t/_s_e_n_d _s_c_r_i_p_t.  The same syntax is
     used in the _L-_d_e_v_i_c_e_s file to interact with the dialer prior
     to making a connection; there it is referred to as a _c_h_a_t
     _s_c_r_i_p_t.  The complete format for one _e_x_p_e_c_t/_s_e_n_d pair is:

	  _e_x_p_e_c_t-_t_i_m_e_o_u_t-_s_e_n_d-_e_x_p_e_c_t-_t_i_m_e_o_u_t   _s_e_n_d

     _E_x_p_e_c_t and _S_e_n_d are character strings.  _E_x_p_e_c_t is compared
     against incoming text from the remote host; _s_e_n_d is sent
     back when _e_x_p_e_c_t is matched.  By default, the _s_e_n_d is fol-
     lowed by a `\r' (carriage return). If the _e_x_p_e_c_t string is
     not matched within _t_i_m_e_o_u_t seconds (default 45), then it is
     assumed that the match failed.  The `_e_x_p_e_c_t-_s_e_n_d-_e_x_p_e_c_t'
     notation provides a limited loop mechanism; if the first
     _e_x_p_e_c_t string fails to match, then the _s_e_n_d string between
     the hyphens is transmitted, and _u_u_c_i_c_o waits for the second
     _e_x_p_e_c_t string. This can be repeated indefinitely. When the
     last _e_x_p_e_c_t string fails, _u_u_c_i_c_o hangs up and logs that the
     connection failed.

     The timeout can (optionally) be specified by appending the
     parameter `~_n_n' to the expect string, when _n_n is the timeout
     time in seconds.

     Backslash escapes that may be imbedded in the _e_x_p_e_c_t or _s_e_n_d
     strings include:

	  \b	  Generate a 3/10 second BREAK.
	  \b_n	  Where _n is a single-digit number;
		  generate an _n/10 second BREAK.



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	  \c	  Suppress the \r at the end of a _s_e_n_d string.
	  \d	  Delay; pause for 1 second. (_S_e_n_d only.)
	  \r	  Carriage Return.
	  \s	  Space.
	  \n	  Newline.
	  \xxx	  Where _x_x_x is an octal constant;
		  denotes the corresponding ASCII character.

     As a special case, an empty pair of double-quotes "" in the
     _e_x_p_e_c_t string is interpreted as ``expect nothing''; that is,
     transmit the _s_e_n_d string regardless of what is received.
     Empty double-quotes in the _s_e_n_d string cause a lone `\r'
     (carriage return) to be sent.

     One of the following keywords may be substituted for the
     _s_e_n_d string:

	  BREAK   Generate a 3/10 second BREAK
	  BREAK_n  Generate an _n/10 second BREAK
	  CR	  Send a Carriage Return (same as "").
	  EOT	  Send an End-Of-Transmission character, ASCII \004.
		  Note that this will cause most hosts to hang up.
	  NL	  Send a Newline.
	  PAUSE   Pause for 3 seconds.
	  PAUSE_n  Pause for _n seconds.
	  P_ODD   Use odd parity on future send strings.
	  P_ONE   Use parity one on future send strings.
	  P_EVEN  Use even parity on future send strings. (Default)
	  P_ZERO  Use parity zero on future send strings.

     Finally, if the _e_x_p_e_c_t string consists of the keyword ABORT,
     then the string following is used to arm an abort trap. If
     that string is subsequently received any time prior to the
     completion of the entire _e_x_p_e_c_t/_s_e_n_d script, then _u_u_c_i_c_o
     will abort, just as if the script had timed out. This is
     useful for trapping error messages from port selectors or
     front-end processors such as ``Host Unavailable'' or ``Sys-
     tem is Down.''

     For example:

	  ""  ""  ogin:--ogin:	nuucp  ssword:	ufeedme

     This is executed as, ``When the remote system answers,
     _e_x_p_e_c_t nothing.  _S_e_n_d a carriage return.  _E_x_p_e_c_t the remote
     to transmit the string `ogin:'. If it doesn't within 45
     seconds, send another carriage return.  When it finally
     does, _s_e_n_d it the string `nuucp'.	Then _e_x_p_e_c_t the string
     `ssword:'; when that is received, _s_e_n_d `ufeedme'.''

FILES
     /etc/uucp/L.sys



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L.SYS(5)	    UNIX Programmer's Manual		 L.SYS(5)



     /etc/uucp/UUAIDS/L.sysL.sys example

SEE ALSO
     uucp(1), uux(1), L-devices(5), services(5), uucico(8)

BUGS
     ``ABORT'' in the send/expect script is expressed ``back-
     wards,'' that is, it should be written `` _e_x_p_e_c_t ABORT'' but
     instead it is `` ABORT _e_x_p_e_c_t''.

     Several of the backslash escapes in the send/expect strings
     are confusing and/or different from those used by AT&T and
     Honey-Danber UUCP.  For example, `\b' requests a BREAK,
     while practically everywhere else `\b' means backspace.
     `\t' for tab and `\f' for formfeed are not implemented.
     `\s' is a kludge; it would be more sensible to be able to
     delimit strings with quotation marks.






































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