ระบบแฟ้ม (File System)

http://www.cs.wisc.edu/~bart/537/lecturenotes/s24.html
The file descriptor information has to be stored on disk, so it will stay around even when the OS does not.
– In Unix, all the descriptors are stored in a fixed size array on disk. The descriptors also contain protection and accounting information.
– A special area of disk is used for this (disk contains two parts: the fixed-size descriptor array, and the remainder, which is allocated for data and indirect blocks).
– The size of the descriptor array is determined when the disk is initialized, and cannot be changed. In Unix, the descriptor is called an i-node, and its index in the array is called its i-number. Internally, the OS uses the i-number to refer to the file.
– When a file is open, its descriptor is kept in main memory. When the file is closed, the descriptor is stored back to disk.
[img]http://www.cs.wisc.edu/~bart/537/lecturenotes/figures/s26.unix.gif + inode.gif + demos-fs.gif[/img]
ext2 : the standard in Linux
ext3 : further development of ext2 (currently beta status), will be able to do journaling

General overview of the Linux file system
http://www.faqs.org/docs/linux_intro/sect_03_01.html
ls -l แสดงจำนวน folder ในแต่ละห้อง
ls -i แสดง inode ของแต่ละแฟ้ม
df -h แสดงพื้นที่แต่ละ partition
[img]http://www.faqs.org/docs/linux_intro/images/FS-layout.png[/img]
ภาพแสดงระบบแฟ้มของ ext2 ในระบบปฏิบัติการ linux
http://www.bb-zone.com/SLGFG/chapter1.html
http://www.cs.wisc.edu/~bart/537/lecturenotes/s24.html
http://www.csie.ntu.edu.tw/~pangfeng/System%20Programming/Lecture_Note_2.htm
http://vandali.org/DanieleMasini/sorgentiinfolinux.php รวมภาพเกี่ยวกับ linux เพียบ
1. Direct blocks
2. Indirect blocks
3. Double indirect blocks
4. Triple indirect blocks
[img] web Inode.gif + demos-fs.gif[/img]

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