Talk:OP CHECKSIG

Redundant step?

Under "How it works", we have steps 2 and 6:

- 2. A new subscript is created from the instruction from the most recent OP_CODESEPARATOR to the end of the script. If there is no OP_CODESEPARATOR the entire script becomes the subscript (hereby referred to as subScript)

- 6. All OP_CODESEPARATORS are removed from subScript

However, doesn't step 6 seem redundant? Vegard

Answer: (sirk390) The comment for step 6. in the bitcoin sources help to understand this (script.cpp:882)

      // In case concatenating two scripts ends up with two codeseparators,
      // or an extra one at the end, this prevents all those possible incompatibilities. 

In step 2, only OP_CODESEPARATOR before OP_CHECKSIG are removed. In step OP_CODESEPARATOR after OP_CHECKSIG are also removed.

More info

Maybe add short description from here Contracts#Theory for all SIGHASH_*? Mad

Code samples and raw dumps

I think there is some error in the section "Code samples and raw dumps" - The input script is:

"04 11 db 93 e1 dc db 8a 01 6b 49 84 0f 8c 53 bc 1e b6 8a 38 2e 97 b1 48 2e ca d7 b1 48 a6 90 9a 5c b2 e0 ea dd fb 84 cc f9 74 44 64 f8 2e 16 0b fa 9b 8b 64 f9 d4 c0 3f 99 9b 86 43 f6 56 b4 12 a3 ac"

and should probably be "304402204e45e16932b8af514961a1d3a1a25fdf3f4f7732e9d624c6c61548ab5fb8cd410220181522ec8eca07de4860a4acdd12909d831cc56cbbac4622082221a8768d1d0901", at least according to the Block Explorer: http://blockexplorer.com/rawtx/f4184fc596403b9d638783cf57adfe4c75c605f6356fbc91338530e9831e9e16 --ThePiachu 22:46, 21 March 2012 (GMT)