Solution:

Windows XP Threads:

• Windows XP implements the Win32 API. The Win32 API is the primary API for the family of Microsoft operating systems (Windows 95, 98, NT, 2000, and XP).

• A Windows XP application runs as a separate process, and each process may contain one or more threads.

• Indeed, much of what is mentioned in this section applies to this entire family of operating systems.

• Windows XP uses the one-to-one mapping described in win threads. , Windows XP also provides support for a fiber library, which provides the functionality of the many-to-many model.

• By using, the thread library, any thread belonging to a process can access the address space of the process.

The general components of a thread include:

• A register set representing the status of the processor.

• A user stack, employed when the thread is running in user mode, and a kernel stack, employed when the thread is running in kernel mode.

• A thread ID uniquely identifying the thread.

• A private storage area used by various run-time libraries and dynamic link libraries (DLLs).

• The register set, stacks, and private storage area are known as the context of the thread. The primary data structures of a thread include:

ETHREAD—executive thread block:

• The key components of the ETHREAD include a pointer to the process to which the thread belongs and the address of the routine in which the thread starts control.

KTHREAD—kernel thread block:

• The KTHREAD includes scheduling and synchronization information for the thread.

• In addition, the KTHREAD includes the kernel stack (used when the thread is running in kernel mode) and a pointer to the TEB.

TEB—thread environment block:

• The TEB is a user-space data structure that is accessed when the thread is running in user mode.

• Among other fields, the TEB contains the thread identifier, a user-mode stack, and an array for thread specific data (which Windows XP terms thread-local storage).

• The structure of a Windows XP thread is illustrated in Figure.