user44137: I am building a website which involves in the processing of transactions of BTC. My current and most efficient plan to complete this would be to call these bitcoin-cli commands and process the data accordingly: 
getblockcount - get block height 
getblockhash blockheight-5 - get the block hash for the last 5 blocks 
listsinceblock blockhash - list all transactions since then
I would run this order of commands every 5-10 seconds. I would like to know if this method wont screw me over at all (skipping transactions, etc). I might just be too paranoid about clients not getting what they paid for and just want a guaranteed method that no transactions slip by. I was hoping to call a method that can list all transactions since a certain time but that wasn't available. Now to the question: 
Is this method CPU/Network intensive?
Is it a safe method?
What are my alternatives?

user44137: I have found the answer to my own question
To make sure every transaction goes through my script I have decided to use walletnotify. This is a feature of bitcoind and will run a bash script every time there is a new transaction with the transaction id. I was able to place this in my .bitcoin/bitcoin.conf file with the parameters like so:
walletnotify=/bin/echo %s | /bin/nc -U /root/nodejs.sock
I used netcat to bridge my requests from bash to NodeJS however you can use your %s transaction data any way you like.

44137: <p>I am building a website which involves in the processing of transactions of BTC. My current and most efficient plan to complete this would be to call these bitcoin-cli commands and process the data accordingly: <br/>
<code>getblockcount</code> - get block height <br />
<code>getblockhash blockheight-5</code> - get the block hash for the last 5 blocks <br />
<code>listsinceblock blockhash</code> - list all transactions since then<br></p>

<p>I would run this order of commands every 5-10 seconds. I would like to know if this method wont screw me over at all (skipping transactions, etc). I might just be too paranoid about clients not getting what they paid for and just want a guaranteed method that no transactions slip by. I was hoping to call a method that can list all transactions since a certain time but that wasn't available. Now to the question: <br /></p>

<p>Is this method CPU/Network intensive?<br/>
Is it a safe method?<br />
What are my alternatives?</p>
 44137: <p><strong>I have found the answer to my own question</strong><br />
To make sure every transaction goes through my script I have decided to use <code>walletnotify</code>. This is a feature of <code>bitcoind</code> and will run a bash script every time there is a new transaction with the transaction id. I was able to place this in my <code>.bitcoin/bitcoin.conf</code> file with the parameters like so:<br />
<code>walletnotify=/bin/echo %s | /bin/nc -U /root/nodejs.sock</code><br />
I used netcat to bridge my requests from bash to NodeJS however you can use your <code>%s</code> transaction data any way you like.</p>
