Basics of Directories

A directory is a set of file names, supporting lookup by symbolic name.

In Nachos, each directory is a file containing

a set of mappings from name->FileHdr.

sector 32

Directory(entries)

sector = Find(name)

Add(name, sector)

Remove(name)

Each directory entry is a fixed-size

slot with space for a FileNameMaxLen byte name.

Entries or slots are found by a linear scan.

A directory entry may hold a pointer to another directory,

forming a hierarchical name space.