ka9qnos.txt

uCLinux下的一个TCP/IP协议栈源码

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3.31.6.  ifconfig <iface> linkaddress <hardware-dependant>

Set the hardware dependant address for this interface.

3.31.7.  ifconfig <iface> mtu <mtu>

Set the MTU for this interface.  See the Setting ... MTU, MSS and
Window chapter for more information.

3.31.8.  ifconfig <iface> netmask <address>

Set the sub-net mask for this interface.  The <address> takes the
form of an IP address with 1's in the network and subnet parts of
the address, and 0's in the host part of the  address.   This  is
related  to  the  broadcast sub-command.  See also the route com-
mand.

3.31.9.  ifconfig <iface> rxbuf <?>

Not yet implemented.

3.32.  ip ...

These commands configure the Internet Protocol (IP) service.

3.32.1.  ip address [<hostid>]

Display or set the default local IP address. This command must be
given before an attach command if it is to be used as the default
IP address for the interface.

3.32.2.  ip rtimer [<seconds>]

Display or set the IP  reassembly  timeout.  The  default  is  30
seconds.

3.32.3.  ip status

Display Internet Protocol (IP) statistics, such as  total  packet
counts and error counters of various types.

3.32.4.  ip ttl [<hops>]

Display or set the time-to-live value placed in each outgoing  IP
datagram.   This  limits  the  number of switch hops the datagram
will be allowed to take. The idea is to bound the lifetime of the
packet  should  it  become  caught in a routing loop, so make the
value slightly larger than the number of hops across the  network
you expect to transit packets.  The default is set at compilation
time to the official recommended value for the Internet.

3.33.  isat [on | off]

Display or set the AT flag.  Currently, there is no sure-fire way



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to  determine  the  type of clock-chip being used.  If an AT type
clock is in use, this command will allow measurement of  time  in
milliseconds,  rather than clock ticks (55 milliseconds per clock
tick).

3.33.1.  kick [<session>]

Kick all sockets associated with a session;  if  no  argument  is
given,  kick  the current session.  Performs the same function as
the ax25 kick and tcp kick commands, but is easier to type.

3.34.  log [stop | <filename>]

Display or set the filename for logging server sessions. If  stop
is  given  as  the  argument,  logging is terminated (the servers
themselves are unaffected).  If a file name is given as an  argu-
ment, server session log entries will be appended to it.

3.35.  mbox

Display the status of the mailbox server system (if configured).

3.36.  memory ...

These commands are used to display memory allocation statistics.

3.36.1.  memory free

Display the storage allocator free list. Each entry consists of a
starting address, in hex, and a size, in decimal bytes.

3.36.2.  memory ibuffs

Display or set the number of  buffers  on  the  interrupt  buffer
pool.  The default is 5.

3.36.3.  memory ibufsize

Display or set the size of each buffer on  the  interrupt  buffer
pool.   Since  the  interrupt  buffer pool consists of fixed-size
buffers, the value chosen must be large  enough  to  satisfy  the
needs of the most demanding driver. The default is 2048.

3.36.4.  memory sizes

Display a histogram of storage allocator request sizes. Each his-
togram bin is a binary order of magnitude (i.e., a factor of 2).

3.36.5.  memory status

Display a summary of storage allocator statistics. The first line
shows the base address of the heap, its total size, the amount of
heap memory available in bytes and as a percentage of  the  total
heap  size,  and the amount of memory left over (i.e., not placed



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on the heap at startup) and therefore available for shell subcom-
mands.

The second line shows the total number of calls to  allocate  and
free  blocks of memory, the difference of these two values (i.e.,
the number of allocated blocks outstanding), the number of  allo-
cation  requests  that were denied due to lack of memory, and the
number of calls to free() that attempted to free garbage (eg.  by
freeing the same block twice or freeing a garbled pointer).

The third line shows the number of calls to malloc and free  that
occurred  with  interrupts off. In normal situations these values
should be zero.  The fourth line shows statistics for the special
pool of fixed-size buffers used to satisfy requests for memory at
interrupt time. The variables shown are  the  number  of  buffers
currently  in  the  pool,  their size, and the number of requests
that failed due to exhaustion of the pool.

3.37.  mkdir <dirname>

Create a sub-directory in the current working directory.

3.38.  mode <iface> [vc | datagram]

Control the default transmission  mode  on  the  specified  AX.25
interface. In datagram mode, IP packets are encapsulated in AX.25
UI frames and transmitted without any other  link  level  mechan-
isms, such as connections or acknowledgements.

In vc (virtual circuit) mode,  IP  packets  are  encapsulated  in
AX.25  I  frames and are acknowledged at the link level according
to the AX.25 protocol.  Link  level  connections  are  opened  if
necessary.

In both modes, ARP is used to map IP  to  AX.25  addresses.   The
defaults can be overridden with the type-of-service (TOS) bits in
the IP header. Turning on the "reliability" bit causes  I  frames
to  be used, while turning on the "low delay" bit uses UI frames.
(The effect of turning on both bits is undefined and  subject  to
change).

In both modes, IP-level fragmentation is done if the datagram  is
larger  than  the  interface  MTU.  In virtual circuit mode, how-
ever, the resulting datagram (or fragments) is further fragmented
at  the  AX.25  layer  if  it (or they) are still larger than the
AX.25 paclen parameter. In  AX.25  fragmentation,  datagrams  are
broken into several I frames and reassembled at the receiving end
before being passed to IP. This is preferable to IP fragmentation
whenever  possible  because  of decreased overhead (the IP header
isn't repeated in each fragment) and increased robustness (a lost
fragment is immediately retransmitted by the link layer).






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3.39.  more <file> [<file> ...]

Display the specified file(s) a screen at a time. To  proceed  to
the  next screen, press the space bar; to cancel the display, hit
the 'q' key.  The more command creates a  session  that  you  can
suspend and resume just like any other session.

3.40.  param <iface> [<param> [value]] ...

Invoke a device-specific control routine.  The following  parame-
ter  names  are  recognized by the parameter command, but not all
are supported by each device type. Most commands deal  only  with
half-duplex packet radio interfaces.

        TxDelay - transmit keyup delay
        Persist - P-persistence setting
        SlotTime - persistence slot time setting
        txTail - transmit done holdup delay
        FullDup - enable/disable full duplex
        Hardware - hardware specific command
        TxMute - experimental transmit mute command
        DTR - control Data Terminal Ready (DTR) signal to modem
        RTS - control Request to Send (RTS) signal to modem
        Speed - set line speed
        EndDelay
        Group
        Idle
        Min
        MaxKey
        Wait
        Down - drop modem control lines
        Up - raise modem control lines
        Return - return a KISS TNC to command mode


Depending on the interface, some parameters can be read  back  by
omitting  a  new  value.  This  is not possible with KISS TNCs as
there are no KISS  commands  for  reading  back  previously  sent
parameters.

On a KISS TNC interface, the param command  generates  and  sends
control  packets  to the TNC.  Data bytes are treated as decimal.
For example, param ax0 txdelay 255   will  set  the  keyup  timer
(type  field  =  1)  on  the  KISS  TNC configured as ax0 to 2.55
seconds (255 x .01 sec).  On all asy interfaces (slip, kiss/ax25,
nrs, ppp) the param <iface> speed command allows the baud rate to
be read or set.

The implementation of this  command  for  the  various  interface
drivers is incomplete and subject to change.

3.41.  ping <hostid> [<length> [<seconds> [<incflag>]]]

Ping (send ICMP Echo Request packets to) the specified  host.  By



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default  the data field contains only a small timestamp to aid in
determining round trip time; if the optional length  argument  is
given,  the  appropriate  number of data bytes (consisting of hex
55) are added to the ping packets.

If interval is specified, pings will be repeated indefinitely  at
the  specified  number of seconds; otherwise a single, "one shot"
ping is done.  Responses to one-shot pings appear  asynchronously
on the command screen, while repeated pings create a session that
may be suspended and resumed.  Pinging continues until  the  ses-
sion is manually reset.

The incflag option causes a repeated ping to increment the target
IP  address  for  each  ping;  it  is an experimental feature for
searching blocks of IP addresses for active hosts.

3.42.  ppp ...

These commands are used to  configure  Point  to  Point  Protocol
interfaces.

This implementation of PPP is designed to be as complete as  pos-
sible.   Because  of  this,  the  number of options can be rather
daunting.  However, a typical PPP configuration might include the
following commands:

        attach asy 0x3f8 4 ppp pp0 4096 1500 9600 r
        dial pp0 dialer.pp0 30
        #
        ppp pp0 quick
        ppp pp0 lcp open
        #
        route add default pp0


3.42.1.  ppp <iface>

Display the status of the PPP interface.

3.42.2.  ppp <iface> quick

Quick setup for the PPP link.  By popular demand, this command is
a shortcut for the following commands:

        ppp pp0 ipcp local compress tcp 16 1
        ppp pp0 ipcp open
        ppp pp0 lcp local accm 0
        ppp pp0 lcp local acfc on
        ppp pp0 lcp local pfc on
        ppp pp0 lcp local magic on







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3.42.3.  ppp <iface> lcp ...

These commands are used for the LCP [Link Control Protocol]  con-
figuration.

3.42.3.1.  ppp <iface> lcp close

Shutdown the PPP interface.

3.42.3.2.  ppp <iface> lcp local ...

These commands control the configuration of the local side of the
link.   If an option is specified, the parameters will be used as
the initial values in configuration requests.  If not  specified,
that option will not be requested.

For each of these options, the allow parameter  will  permit  the
remote  to  include  that  option  in its response, even when the
option is not included in the request.  By default,  all  options
are allowed.

3.42.3.2.1.  ppp <iface> lcp local accm [ <bitmap> | allow [on  |
off] ]

Display or set the Async Control Character Map.  The  default  is
0xffffffff.

3.42.3.2.2.  ppp <iface> lcp local authenticate [ pap  |  none  |
allow [on | off] ]

Display or set the authentication protocol.  The default is none.

3.42.3.2.3.  ppp <iface> lcp local acfc [ on | off | allow [on  |
off] ]

Display or set the option to compress  the  address  and  control
fields  of the PPP HLDC-like header.  This is generally desirable
for slow asynchronous links, and undesirable for fast or synchro-
nous links.  The default is off.

3.42.3.2.4.  ppp <iface> lcp local pfc [ on | off | allow  [on  |
off] ]

Display or set the option to compress the protocol field  of  the
PPP HLDC-like header.  This is generally desirable for slow asyn-
chronous links, and undesirable for fast  or  synchronous  links.
The default is off.

3.42.3.2.5.  ppp <iface> lcp local magic [ on | off |  <value>  |
allow [on | off] ]

Display or set the initial Magic  Number.   The  default  is  off
(zero).