File attributes are kept in the directory structure.
File checksum is one example of an extended file attribute.
"File" is an abstract data type. There is some operation about it, for example: Repositioning within a file and truncating a file.
Repositioning within a file is also known as a file seek.
After opening a file, the operating system keeps several pieces of data to manage open files:
Open-file table, file pointer(including last read/write location), file-open count, disk location of the file, access rights.
Some operating systems and file systems provide file locking. It's similar to reader-writer locks. A shared lock is like a reader lock, an exclusive lock is like writer lock.
There are multiple access methods. Sequential access can only access the current position. Direct access can access files by relative block number.
The directory structure is actually a collection of nodes containing information about all files. Each node corresponds to a file.
*Details about disk structure.
Acyclic-graph directories, general graph directory.
Failure modes
File checksum is one example of an extended file attribute.
"File" is an abstract data type. There is some operation about it, for example: Repositioning within a file and truncating a file.
Repositioning within a file is also known as a file seek.
After opening a file, the operating system keeps several pieces of data to manage open files:
Open-file table, file pointer(including last read/write location), file-open count, disk location of the file, access rights.
Some operating systems and file systems provide file locking. It's similar to reader-writer locks. A shared lock is like a reader lock, an exclusive lock is like writer lock.
There are multiple access methods. Sequential access can only access the current position. Direct access can access files by relative block number.
The directory structure is actually a collection of nodes containing information about all files. Each node corresponds to a file.
*Details about disk structure.
Acyclic-graph directories, general graph directory.
Failure modes
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