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Session 26 - April 09, 2003
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AGENDA:
0 Admin
1 Ch 5.6 (cont.)

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0 - ADMIN
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Startout Q: How does the file system handle system 
calls?

Due today
* RI #8 (web page incorrectly listed as 7)

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1 - CH 5.6 (CONT.)
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BIT MAPS
* track i-nodes and zones

I-NODES
* fig 5-30 p. 461

BLOC CACHE
* fig 5-31 p. 462

DIRECTORIES & PATHS
* 16 bytes, 2 for I-node + 14 for name
* fig 5-32 p. 464

FILE DESCRIPTORS
* fig 5-33 p. 466
* where does file pointer go?
  - not in i-node
  - must have shared pointer between parent and child
  -> separate table

FILE LOCKING
* MINIX supports advisory file locking

PIPES & SPECIAL FILES
* suspend a process if tries reading from a pipe
  and no data is available
* suspend it and restart syscall when data available

Read through code if have time.
* pp. 828-834

COS 421 - Lecture Notes #26		SPRING 2003	
COS421-lect-2003-04-09	Page 1	Printed 09.04.03