Difference between revisions of "File"

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m (New page: A file is an object in a filesystem consisting of two parts, an inode (also called metadata) and the actual contents of the file. A file can have multiple links meaning on the same [[...)
 
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A file is an object in a filesystem consisting of two parts, an [[inode]] (also called metadata) and the actual contents of the file.  A file can have multiple links meaning on the same [[filesystem]] the same file exists more than once with different names, that's why filenames aren't stored in the meta data but rather in directories that hold count of files in them.
 
A file is an object in a filesystem consisting of two parts, an [[inode]] (also called metadata) and the actual contents of the file.  A file can have multiple links meaning on the same [[filesystem]] the same file exists more than once with different names, that's why filenames aren't stored in the meta data but rather in directories that hold count of files in them.
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== The 25 year old bug ==
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Recently this month in May 2008 an OpenBSD developer found a bug in the fast filesystem that was 25 years old.  This means that it isn't exclusively in OpenBSD but all BSD derived OS's.  The bug involved deleting files and directory listings.  Pretend someone read a directory to a certain point and then deleted a file and rewound the directory listing to start new.  If the file was high on the list it would have caused corruption in the directory listing.
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More about this [http://www.undeadly.org/cgi?action=article&sid=20080508193255 here]
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Latest revision as of 06:26, 24 May 2008

A file is an object in a filesystem consisting of two parts, an inode (also called metadata) and the actual contents of the file. A file can have multiple links meaning on the same filesystem the same file exists more than once with different names, that's why filenames aren't stored in the meta data but rather in directories that hold count of files in them.


The 25 year old bug

Recently this month in May 2008 an OpenBSD developer found a bug in the fast filesystem that was 25 years old. This means that it isn't exclusively in OpenBSD but all BSD derived OS's. The bug involved deleting files and directory listings. Pretend someone read a directory to a certain point and then deleted a file and rewound the directory listing to start new. If the file was high on the list it would have caused corruption in the directory listing.

More about this here .