Need Help on clarifying Coinbase transaction:

[Gol]

Hello all.
i did some reading here:
https://en.bitcoin.it/wiki/Protocol_specification.
came across:
"A special kind of transaction, called a coinbase transaction, has no inputs. It is created by miners, and there is one coinbase transaction per block. Because each block comes with a reward of newly created Bitcoins (e.g. 50 BTC for the first 210,000 blocks), the first transaction of a block is, with few exceptions, the transaction that grants those coins..."

any info about: "few exceptions" will be much appreciated.

Cheers,
Gol.

[Gol]

bump...

[Altoidnerd]

Well, now we have to find if there are any blocks whose first tx is not the coinbase.

blockexplorer.com/b/0

blockexplorer.com/b/1

python

Code:

from urllib2 import Request, urlopen, URLError

prompt = '>>'

print "Enter block height"

height = raw_input(prompt)

key = 'http://blockexplorer.com/b/%s' % height

request = Request(key)

try:
	response = urlopen(request)
	block_data = response.read()
	print block_data
except URLError, e:
    print 'whoops', e

mmm need to iterate the block height.  but first im going to figure out how to check if the coinbase is the first tx in a given block.  

[Gol]

not sure i understand...is there a situation that the first tx is NOT coinbase?

[Altoidnerd]

I don't know that's why I want to crawl the blockchain to find out.

[accape]

You won't find such blocks because Bitcoin Core rejects all blocks whose first transaction is anything else but the coinbase transaction (src/main.cpp line 2300).

[Altoidnerd]

So the wiki can be edited.