in reply to Merging hashes at key match

my @VLANS, @MACS, @INTS);
      push $HASH{$MACS[$mac]}, [$VLANS[$vlan], [$INTS[$int]];

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Here, I assume, you want to store all found VLANS, and MAC addresses, however, instead of pushing them as blobs do this:

In each iteration you get a new $mac, just add one to the hash value of $mac $MACS{$mac}++;

This way, you can get a list back later, like so: @ALL_MACS = sort keys %MACS

AND, you can check if that MAC address came by more than once by checking the value $MACS{$mac}

But instead of that, one trick I often do is or-ing: like so:

When found in mac.txt $MACS{$mac} |= 1;

When found in arp.txt $MACS{$mac} |= 2;

This way, when $MACS{$mac} == 3 it is in both. And it can be multiple times in either one of them, the value is still 3.

Storing your data.

# make the data a string
$value = join("|", $VLAN, $MAC, $INT);

# put them into a 1 dimentional hash (however, servers with the same m
+ac hash overwrite each other, although you can check)
if( defined $HASH{$mac} ) {
 warn "Two servers with the same $mac";
}else{
 $HASH{$mac}=$value; 
}

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This way, you can iterate later over your $mac with:

for my $mac (keys %HASH){
  my $value = $HASH{$mac};
  ($VLAN, $MAC, $INT) = split("|", $value);
}

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# or put them in a multi-dimensional hash.
$HASH{$mac}{$value}++;

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This way, you can iterate later over your $mac with:

for my $mac (keys %HASH){
  for my $value (keys %{$HASH{$mac}}){
  }
}

[download]

Now post some example mac.txt and arp.txt so we can really help you.

Replies are listed 'Best First'.
Re^2: Merging hashes at key match
by GeorgMN (Acolyte) on Mar 23, 2016 at 08:48 UTC
    Thank you all kindly for you input! Georg
[reply]
Re^2: Merging hashes at key match
by GeorgMN (Acolyte) on Mar 23, 2016 at 14:19 UTC

    Content of the files i am trying to combine, or at least add the IP address to physical interface together:

    [gtreptow@nostromo show_outputs]$ cat *arp* | grep 10\.60
ARPA   Vlan2010
Internet  10.60.198.59            1   d8d3.85a5.e3c4  ARPA   Vlan198
Internet  10.60.226.31            0   0050.56b0.3d17  ARPA   Vlan2260
Internet  10.60.227.25            1   0050.56b0.7e6e  ARPA   Vlan2270
Internet  10.60.226.24            0   0050.56b0.3580  ARPA   Vlan2260
Internet  10.60.228.31            2   0050.56b0.3569  ARPA   Vlan2280
Internet  10.60.226.25            0   0050.56b0.7fb0  ARPA   Vlan2260
Internet  10.60.249.1             1   0009.0f09.0a01  ARPA   Vlan2490
Internet  10.60.198.62            3   18a9.0559.c862  ARPA   Vlan198
Internet  10.60.197.61            1   0015.1766.1cc8  ARPA   Vlan1970
Internet  10.60.227.26            0   0050.56b0.7f8a  ARPA   Vlan2270
Internet  10.60.197.60            2   047d.7b4a.70ee  ARPA   Vlan1970
Internet  10.60.226.27            0   0050.56b0.19a3  ARPA   Vlan2260
Internet  10.60.250.28            4   001b.90f0.67c1  ARPA   Vlan250
Internet  10.60.249.31            0   d89d.67f4.495c  ARPA   Vlan2490
Internet  10.60.227.5             -   0008.e3ff.fd90  ARPA   Vlan2270

[gtreptow@nostromo show_outputs]$ cat hcs51-4_sh_mac_add.txt 
HCS51-4# sh mac address-table | ex Po24
Legend: 
        * - primary entry, G - Gateway MAC, (R) - Routed MAC, O - Over
+lay MAC
        age - seconds since last seen,+ - primary entry using vPC Peer
+-Link
   VLAN     MAC Address      Type      age     Secure NTFY   Ports/SWI
+D.SSID.LID
---------+-----------------+--------+---------+------+----+-----------
+-------
* 3920     000c.2999.7b8c    dynamic   0          F    F  Eth101/1/33
* 3920     000c.29b5.f5b3    dynamic   0          F    F  Eth101/1/33
* 3920     0014.a998.c962    dynamic   0          F    F  Eth102/1/27
* 2491     0050.56b0.3858    dynamic   0          F    F  Eth101/1/5
* 2491     0050.56b0.5c3e    dynamic   20         F    F  Eth101/1/5
* 2491     0050.56b0.608e    dynamic   0          F    F  Eth101/1/5
* 2491     0050.56b0.66fc    dynamic   0          F    F  Eth101/1/5
* 2491     0050.56b0.7d2b    dynamic   0          F    F  Po21
* 2491     0050.56b0.7e40    dynamic   0          F    F  Eth101/1/5
* 2491     d89d.67f4.495c    dynamic   0          F    F  Eth101/1/15
* 2280     0050.56b0.52e8    dynamic   0          F    F  Po21
* 2280     0050.56b0.57df    dynamic   0          F    F  Eth101/1/14
* 2280     0050.56b0.7258    dynamic   0          F    F  Po21
* 2280     0050.56b0.7e80    dynamic   0          F    F  Po21
* 2280     0050.56b0.7f99    dynamic   0          F    F  Po21
* 2280     0050.56b0.7f9a    dynamic   0          F    F  Po21
* 2280     0050.56b0.7fe5    dynamic   0          F    F  Po21
* 2271     0050.56b0.1186    dynamic   0          F    F  Eth101/1/5
* 2271     0050.56b0.1eee    dynamic   10         F    F  Eth101/1/5
* 2271     0050.56b0.24f1    dynamic   0          F    F  Eth101/1/14
* 2271     0050.56b0.7e6e    dynamic   0          F    F  Eth101/1/5
* 2271     0050.56b0.7f8a    dynamic   0          F    F  Eth101/1/5
* 2261     0050.56b0.221d    dynamic   0          F    F  Eth101/1/14
* 2261     0050.56b0.357f    dynamic   0          F    F  Eth101/1/14
* 2261     0050.56b0.7e59    dynamic   0          F    F  Eth101/1/14
* 2261     0050.56b0.7f8e    dynamic   0          F    F  Eth101/1/14
* 2260     0050.56b0.19a3    dynamic   0          F    F  Eth101/1/14
* 2260     0050.56b0.7de5    dynamic   0          F    F  Eth101/1/14
* 2240     0050.56b0.0010    dynamic   0          F    F  Eth101/1/14
* 2240     0050.56b0.0012    dynamic   0          F    F  Eth101/1/14
* 2240     0050.56b0.2556    dynamic   0          F    F  Eth101/1/14
* 2240     0050.56b0.6261    dynamic   0          F    F  Eth101/1/14
* 2040     0050.56b0.002f    dynamic   100        F    F  Eth101/1/14

[gtreptow@nostromo show_outputs]$ 
... and so on....

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[d/l]
      How about this? (I tried to made it simple and readable, instead of terse. But ask if you do not understand a part, or do not know how to extend it to what you need)

      #!/usr/bin/perl
use strict;
use warnings;

my @FILENAMES_ARP = <./*arp*.txt>;
my @FILENAMES_MAC = <./*mac*.txt>;
# use File::Slurp;    this way this works:  my @LINES =read_file($FILE
+ );
my %MACS;
my $FILE;


my $CLEAN_ARP_REC = './clean_arp.tmp';
open (OUTPUT, ">", $CLEAN_ARP_REC) or die "Could not open $CLEAN_ARP_R
+EC because $!"; 

for $FILE (@FILENAMES_MAC){
    print "processing $FILE...\n";
    if( open(FH, "<", $FILE) ){
        while(<FH>){
            chomp;
            next unless /^\*/; # skip if line does not start with "*",
+ for example, empty lines
            next if /static/; # skip static entries
            my @F = split(/\s+/, $_);
            my $VLAN = $F[1];
            my $MAC =$F[2];
            my $INT = $F[7];
            next unless $MAC=~/^[0-9a-f]{4}\.[0-9a-f]{4}\.[0-9a-f]{4}$
+/;
            if($MACS{$MAC}){
                warn "$MAC already defined, skipping entry at line $.\
+n";
            }else{
                $MACS{$MAC}{VLAN}=$VLAN;
                $MACS{$MAC}{INT}=$INT;
            }
        }
        close FH;
    }else{
        warn "Could not open $FILE, skipping. Errormsg=$!\n";
    }
}    

for $FILE (@FILENAMES_ARP){
    print "Processing $FILE...\n";
    if( open(FH, "<", $FILE) ){
        while(<FH>){
            chomp;
            my @F = split(/\s+/, $_);
            my $MAC = $F[3];
            my $VLAN = $F[5];
            my $IP = $F[1];
            next unless $IP; # must be defined?
            if($MACS{$MAC}){
                $MACS{$MAC}{IP}=$IP; # add this extra data
                $MACS{$MAC}{_}=1; # have to "merge"
            }
        }
        close FH;
    }else{
        warn "Could not open $FILE, skipping. Errormsg=$!\n";
    }
}

for my $MAC (sort keys %MACS){
    if( defined $MACS{$MAC}{_} ){
        print OUTPUT $MAC 
            . ", " . $MACS{$MAC}{IP}
            . ", " . $MACS{$MAC}{VLAN}
            . ", " . $MACS{$MAC}{INT}
            ."\n";
    }else{
        # normal line, do not print ?    
    }
}

close OUTPUT;

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[reply]
[d/l]

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