# File - File

A file is a logical representation of multiple block that can be accessed and manipulated at once by a program.

A file is durable in the sense that it remains available for programs to use after the current program has finished.

## 3 - Properties

A file has three important attributes:

• directory (act as a namespace)
• and contents.

A file consists also of attributes such as:

• the extend attributes,
• and the timestamps on the file.

Example of properties from the Linux stat utility

  File: testFile.txt'
Size: 4               Blocks: 8          IO Block: 4096   regular file
Device: ca02h/51714d    Inode: 2522975     Links: 1
Access: (0644/-rw-r--r--)  Uid: (  500/  oracle)   Gid: ( 1001/oinstall)
Access: 2015-09-15 13:50:26.000000000 +0200
Modify: 2015-09-15 12:43:18.000000000 +0200
Change: 2015-09-15 12:43:18.000000000 +0200`

## 4 - Open

List of open files: see IO - Diagnostic/Monitoring

File handles (open file) are scarce, finite resources. Because they are loaded in memory, the maximum number of open file is always a parameter of the file system (Generally in the OS). You can them run out of them if you don't close in your application the stream (ie the in-memory file representation of a file) up properly, just like database connections.

## 5 - Management

### 5.2 - Location

The location of a file is given:

• logically by its path
• that the file system physically translate to an address on the file store

## 6 - Glossary

### 6.1 - Binary

Binary generally means proprietary non textual data. See Bit - Binary Data (Structure)