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Kernel Directory Structure

In Linux the Kernel source is available under /usr/src/linux.

  • Architecture dependent code is available in the following directory structure

    • arch/alpha – for the DEC Alpha Architecture
    • arch/x86 – for the Intel 32 bit Architecture
    • arch/arm – for the ARM Architecture
    • arch/ia64 – for the intel 64 bit architecture
    • arch/m68k – for the 68000 architecture and compatible processors. 
  • init/ directory contains all the functions needed to start the kernel.  
  • kernel/ – central sections of the kernel. Most important system calls are implemented here. 
  • arch/x86/mm or mm/ – takes care of memory management by requesting and releasing kernel memories.  
  • fs/ is the virtual file system interface. Some important file systems are proc, ext2,ext3,. The proc file systems is used for system management. 
  • drivers/ – every operating system requires drivers for its hardware components. These are held in this directory and classified into groups according to their subdirectories like the following

    • drivers/char – character oriented devices
    • drivers/block – block oriented devices
    • drivers/i2c – a generic i2c driver
    • drivers/scsi – the SCSI interface
    • drivers/usb – drivers for the USB subsystem 
  • ipc/ – indicates the Inter process communication  
  • lib/ – indicates the standard C library functions

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