startslip(8)startslip(8)NAMEstartslip - Configures SLIP connections
SYNOPSIS
/usr/sbin/startslip [-i filename]
OPTIONS
Specifies the file containing the startslip subcommands for dial-out
connections.
DESCRIPTION
The startslip program configures two types of SLIP connections: Dial-in
connections -- The system is to answer calls from remote systems.
Dial-out connections -- The system is to place calls to a remote sys‐
tem.
Dial-in Connections
If your system is configured as a dial-in system, a getty process is
continuously run on the serial line that is connected to a modem. When
a call comes in, getty prompts for a login name. If the login name
matches a SLIP user name entry in the /etc/passwd file, getty starts
startslip as a login shell. The startslip program then reads the
/etc/slhosts files until it finds an entry matching the current login
name. If an entry is found, startslip configures the tty line as a
SLIP link using information in the slhosts file entry.
See Network Administration: Connections for information on setting up
your system as a SLIP dial-in system.
Dial-out Connections
If your system is configured as a dial-out system and you want to cre‐
ate a SLIP connection to a remote system, you invoke the startslip pro‐
gram from the command line and specify -i filename. The filename file
contains the startslip subcommands to set up the dial-out connection
(see the Subcommands section). After making the connection, startslip
runs in the background.
When you are finished with the SLIP connection, you can either turn off
your modem or kill the tty process. The tty process ID is stored in
the /var/run/ttyxx.tel-pid file, where ttyxx specifies the terminal
line.
Subcommands
The following startslip subcommands can be used to set up SLIP dial-out
connections. The subcommands are specified in a SLIP setup script file
that is passed to startslip with the -i filename option. In the setup
script file, any text following the comment character (#) is ignored.
In addition, each line can contain up to 256 characters. Specifies the
callback option. If this subcommand is specified, startslip raises
Data Terminal Ready (DTR) if carrier is lost during a read from the
serial line. Causes startslip to configure the network interface with
the values specified with the myip, dstip, and netmask subcommands, and
to attach the serial line to the network interface. If the gateway is
specified, it also adds the destination IP address as the default gate‐
way.
Specify this subcommand at the end of the script file. Specify
the myip, dstip, netmask, and, optionally, gateway subcommands
prior to connslip. Enables debugging and prints debug messages
to the logfile file. Specify this subcommand at the beginning of
the script file. Dials the telephone_number. The format of
telephone_number is a string of numbers with no separators.
Specify this subcommand after opentty and modemtype. Sets des‐
tination IP address. You can specify either a host name or IP
address. Terminates startslip and exits. Causes startslip to
wait to receive string from the remote host. If a match occurs,
startslip continues reading this file. If a match does not
occur after the specified seconds, startslip prints message and
exits.
Specify this subcommand after opentty. Flushes the read and
write queues. Sets the destination IP address as the default
gateway. Specifies a hard-wired link. Ignore modem control
signals (CLOCAL flag set in termios structure) when switching to
a SLIP connection. Enables ICMP traffic suppression. Sets the
modem type. The modem_name specified must be defined in the
/etc/acucap file. Sets my local IP address. You can specify
either a host name or IP address. Sets the network mask. Opens
the ttyxx serial line and sets line speed to baud_rate. The
value for baud_rate must be one of the standard speeds listed in
</usr/include/sys/termios.h>. Prints string to the standard
output; everything to the end of the line, including punctua‐
tion, is printed. Use this subcommand to cue the user as to
which subcommand is executing. Causes startslip to read either
the local IP address, destination IP address, or network mask
from the remote system in dotted decimal notation. Use this sub‐
command after opentty. An expect subcommand should be used
prior to raddr ensure that the desired information is read.
Sends the string to the serial line. Use this subcommand after
opentty.
If string is set to the keyword ASKPASSWD, startslip prompts for
a password, reads it from standard input, and sends it to the
serial line. Causes startslip to sleep number_of_seconds before
continuing to read subcommands. Displays current status of
startslip. Enables TCP header compression. Enables automatic
TCP header compression.
RESTRICTIONS
Only a person with superuser authority can run the startslip program.
EXAMPLES
The following sample setup script file shows how to use various start‐
slip dial-out subcommands.
debug /tmp/debuglog
myip 27.140.208.38
dstip 27.140.208.40
netmask 255.255.255.0
# set modemtype before dialing # microcom modem attributes defined in
/etc/acucap modemtype microcom
printmsg open /dev/tty00 at speed 38400 opentty tty00 speed 38400
printmsg dial 18154231234 dial 18154231234
# expect login prompt. timeout and exit after 5 seconds. expect ogin:
timeout 5 errmsg "not getting login: prompt"
printmsg send login send sliplogin
# expect password prompt. timeout and exit after 5 seconds. expect
assword: timeout 5 errmsg "not getting Password: prompt"
printmsg Prompt and send password send ASKPASSWD
# expect Starting SLIP after login expect SLIP timeout 10 errmsg "not
getting startup message"
# connect slip - ifconfig, slattach printmsg connect slip connslip
FILES
Specifies the command path Contains the startslip process ID Specifies
the termios header file
SEE ALSO
Commands: ifconfig(8)
Files: acucap(4), slhosts(4)
Network Administration: Connections
Specifications: A Nonstandard for Transmission of IP Datagrams Over
Serial Lines: SLIP (RFC1055)
Compressing TCP/IP Headers for Low-speed Serial Links (RFC1144)
startslip(8)