Updated 2014-10-07 10:36:52 by Stu

Netinfo - Protocol, service, network, host and ether info

Directions to find it at Stu

Netinfo version 0.6, October 2014.

  • Misc improvements.

Netinfo version 0.5, October 2009.

  • Added "ethers" db

Netinfo version 0.4, September 2007.

  • Added "networks" db
  • A bit of cleanup/adjustment
  • Documentation improvements

2009-01-03 Stu TkNib (Tk Netinfo Browser, included with Netinfo) is a GUI frontend to Netinfo. TkNib loads and displays all available information from the five system databases supported by Netinfo. Columns can be sorted by clicking on their headers. It's a very simple program; an example of working with Netinfo, Ttk, Tk and Tcl. Thanks to dkf's widget demo for the sort proc.

2009-10-01 Stu I removed TkNib from this page; it's included with Netinfo.

Netinfo is also the name of a OS subsystem handling these issues in NEXTSTEP and MacOS X. What relation, if any, is there between that and Stu's package?

Stu sez: No relationship. I was unaware of the NEXTSTEP and MacOS X subsystem until now. Netinfo was originally called Netutil but it turned out to be more info-ish than util-ish. Do you think this will cause any problems? Netinfo 0.3 was released a year ago and I haven't had any complains although I have no idea if anyone is using it.

One example of usage would be to look up hostnames (usually taken from /etc/hosts) using Netinfo and creating sockets (aka ceps) using Ceptcl and the -noresolve option. This way, one can avoid the potential delays caused by the operating system looking up the hostname.

From the man page:
       The netinfo Tcl extension provides access to system protocol, service,
       network, host and ether information which is retrieved from system
       databases and made available for querying.

       This functionality is somewhat analogous to that provided by some of
       the functions referenced in the  C include file usually found
       on unix-like operating systems (gethostbyname, getservbyport, etc).
       Unlike those functions, netinfo does not go beyond referencing the data
       stored in the system databases; netinfo does not access the databases
       per query, rather it loads the data and parses it into an internal
       ready-for-querying format.  If any changes are made to the databases
       after loading then the affected databases would need to be reloaded if
       the changes are to be available to netinfo queries.

       Normal usage involves optionally specifying any database files if the
       defaults do not match your reality, calling as many of the "load"
       commands as are necessary (depending on what data you need to access;
       netinfo does not load anything at startup) and using the querying and
       extraction commands to retrieve info.

       # Results noted with #=>
       package require netinfo
       namespace import ::netinfo::*
       loadProtocolData; loadServiceData; loadNetworkData; loadHostData; loadEtherData

       protocolData [protocol -number 123] -comment
       #=> Performance Transparency Protocol
       protocolData [protocol -number 123] -comment -name
       #=> {Performance Transparency Protocol} ptp

       service -port 9
       #=> discard 9 {sink null} {} tcp
       service -port 9 -protocol udp
       #=> discard 9 {sink null} {} udp
       service -port 9 -protocol *
       #=> {discard 9 {sink null} {} tcp} {discard 9 {sink null} {} udp}
       serviceData [lindex [service -port 9 -protocol *] 1] -protocol -port
       #=> udp 9

       network -number 127
       #=> loopback loop {} 127
       networkData [network -number 224] -name

       hostData [host -aliases localhost] -address
       hostData [host -aliases localhost -domain inet6] -address
       #=> ::1

        etherData [ether -name toaster] -address
       #=> 00:01:6a:e3:df:0a

       # List all services:
       service -name *