PHONE(8)

NAME
phone - MMDF PhoneNet Phone Channel

SYNOPSIS
phone

DESCRIPTION

The phone channel is the active (or master) component of the PhoneNet protocol package. The passive component is the slave program (see slave(8)). Phone establishes a connection to a remote machine's slave by following the instructions contained in a dialing script. The dialing script is specified in the channel's definition in the runtime tailoring file by the scr= parameter. Scripts reside, by default, in the table directory. See script(5) for information about how to construct a dialing script.

Once a connection has been established, the ``start'' command initiates the PhoneNet link-level (dial) protocol. Several dial package parameters are set by commands in the dialing script. The default illegal character sets are typically compiled into conf_dial.c but those defaults may be overridden by using the DBADIN, DBADOUT, or DBAD specifications in the runtime tailoring file (see section 3.13 of the ``Installing and Operating MMDF II'' document). The defaults may be further superseded by specifying replacement illegal character sets in the dialing script. The dial package defaults to a packet window size of 1. It is the master's responsibility to override that default if desired (see the ``window'' command documented in script(5)).

Phone is a two-way channel; mail queued on the local machine is delivered to the remote machine and mail queued on the remote machine is picked up. If deliver is called on a phone channel and mail is queued for that channel, a connection is attempted immediately. If no messages are waiting, then deliver decides whether to invoke the channel to do a pickup of mail from the remote machine. Such a pickup is called a "poll". Deliver looks at the value of the poll= parameter in the phone channel's runtime tailoring file definition to decide whether to initiate a poll. If the value of poll is 0, polls are never performed. If the value is -1, polls are always performed. Otherwise, the value of poll represents the number of 15-minute intervals to wait before doing a poll. For example, if poll=3 and no messages are queued to be sent out, then any deliver's attempted within 45 minutes of the last successful pickup will return immediately without attempting connection to the remote machine.

Once a connection is made with the remote slave, phone sends one of three commands to the slave: submit, pickup, and end. If there are messages waiting to be sent to the remote machine (and if mod=send has been selected on this channel), then the first command phone sends is ``submit''. While submitting messages to the remote slave, phone manages the interface between the dial package and deliver (i.e. the mail queue).

When all waiting messages have been sent, phone sends the ``pickup'' command (if mod=pick has been selected on this channel). While picking up messages from the remote slave, phone passes messages to the local submit program which queues messages on the local machine. The messages are submitted just as if a submit were being done with the slave program. The source channel and host are set according to the values defined for this phone channel.

When the remote slave indicates that all messages have been picked up, phone sends the ``end'' command and resumes processing the dialing script on the line following the ``start'' command.

TROUBLESHOOTING
If a connection to a remote slave cannot be made, check the PHLOG (usually ph.log) for information about why the connection is failing. If possible, try to connect to the remote slave by hand. If the manual attempt fails, you know to go check the modem (or direct line) and the remote machine for problems.

Often a connection will be made with the remote machine but there will be a problem getting to the point where the slave begins the link-level protocol. A common error message to see in PHLOG is: ``Timeout while processing script''. This message indicates that a string expected by a ``recv'' command was not matched within the specified number of seconds. Look in the transcript file (specified by the trn= channel parameter which defaults to DEFTRAN, usually ph.trn) to see why the ``recv'' string was not matched.

Often, noise characters can prevent transmitted strings from being received correctly by the remote host. One trick to reduce the possibility of interference is to precede transmitted lines with the remote machine's line-erase character (e.g. xmit ``@username\r'').

SEE ALSO
script(5), slave(8), deliver(8), submit(8)