note 104836 added to function.hash-file
| From: | apmatdomainitsmee dot co dot uk at osu1 dot php dot net | Date: | Sun, 10 Jul 2011 11:56:14 +0000 |
| Subject: | note 104836 added to function.hash-file | ||
| Groups: | php.notes | ||
| Request: | Send a blank email to php-notes+get-181401@lists.php.net to get a copy of this message | ||
I have verified that the output of the "crc32" is the ITU I.363.5 algorithm (a.k.a. AAL5
CRC - popularised by BZIP2 but also used in ATM transmissions - the algorithm is the same as that in
POSIX 1003.2-1992 in Cksum but that stuffs the size into the CRC at the end for extra measure).
However, the output is expressed in reverse order to many CRC programs. Using the
"standard" crctest.txt (numbers 1 to 9 in sequence - google it, it's not hard to
find), php will output 181989fc - many other (Intel little endian) programs would output this as
fc891918, hence the confusion (that I have had, at least).
The crc32b is the 32-bit Frame Check Sequence of ITU V.42 (used in Ethernet and popularised by
PKZip). The output from this CRC is popularised in Intel little endian format and would produce
cbf43926 on the same file.
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Server IP: 69.147.83.197
Probable Submitter: 81.31.102.232
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Manual Page -- http://www.php.net/manual/en/function.hash-file.php
Edit -- https://master.php.net/note/edit/104836
Del: integrated -- https://master.php.net/note/delete/104836/integrated
Del: useless -- https://master.php.net/note/delete/104836/useless
Del: bad code -- https://master.php.net/note/delete/104836/bad+code
Del: spam -- https://master.php.net/note/delete/104836/spam
Del: non-english -- https://master.php.net/note/delete/104836/non-english
Del: in docs -- https://master.php.net/note/delete/104836/in+docs
Del: other reasons-- https://master.php.net/note/delete/104836
Reject -- https://master.php.net/note/reject/104836
Search -- https://master.php.net/manage/user-notes.php