I use an application called Easy-IP to keep track of IP utilization. Underneath lies a Firebird database, which I've extracted to CSV. The header line lists all the columns, but I wanted to know the array index for processing. Short of counting commas, I came up with: 
head -1 ./current.csv |perl -ane '$i = 0; s/\,/" ".$i++."\n"/eg; print
+;'

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The header line looks like so: 
SUBNET_ID,AUTONOMOUS_NETWORK_ID,PARENT_ID,TREE_PATH,SUBNET,CIDR_MASK,I
+P_VERSION,LOW_ADDRESS,HIGH_ADDRESS,BROADCAST_ADDRESS,SHORT_SUBNET,ASS
+IGNED_ADDRESSES,CHILD_SUBNET_COUNT,COMMENT,SYSTEM_FLAG1,REPLICATED_FR
+OM,CREATED,UPDATED,LOCATION,USAGE,NETWORK_NAME,IP_NETWORK,IP_NETWORK_
+BLOCK,ORGANIZATION,ADMIN_CONTACT,TECH_CONTACT,ORG_NAME,STREET_ADDRESS
+,CITY,STATE,POSTAL_CODE,COUNTRY_CODE,PRIMARY_SERVER,SECONDARY_SERVER

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My output, abbreviated:
SUBNET_ID 0
AUTONOMOUS_NETWORK_ID 1
PARENT_ID 2
TREE_PATH 3
SUBNET 4
...

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I bet the brains at PM can do better. Suggestions?

In reply to enumerate column numbers by cidaris

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