Help cross-referencing files

[David Nicol]

On 4/18/05, Brad <brad at bradandkim.net> wrote:
> Hi all,
> 
> I have 3 files each of which are space delimited sets of data.  I have
> to cross-reference these files to get one set of data at the end.  The
> first file maps IP Address to Cisco ATM interface, the second maps IP
> Address to MAC Address, and the third maps Cisco ATM interface to actual
> VPI and VCI.  I need to map MAC Address to VCI/VPI.  Here is a sample of
> each file:
> 
> 24.121.58.91     0.32
ip to if 
> 24.121.57.11     0100.0f66.2b81.5f
mac to ip
> 0.2     1     33
if to data
> 
> I was thinking of using awk, but I am not sure how to tell awk to keep
> an array for each line of 2 files (let alone 3).  Any shell script
> guru's care to lend some advice?


perl's associative arrays are ideal for this kind of thing,
especially coupled with its easy line-based file primitives.

open IP2IF, "ip_to_interface_file";
while (<IP2IF>){
        /([0123456789\.]+)\s+([0123456789\.]+) or next;
        $ip2if{$1} = $2;
};

repeat something like that for all three, then

for (keys %mac2ip){
      print "Mac Address $_ is handled on ",
      "Vdata $if2data{$ip2if{$mac2ip{$_}}}\n";
};



hope that helps


-- 
David L Nicol
$SesKey=join"",grep{/\w/}map{chr rand 128}0..99;#Zesty!