NOTE

Creating and Using Libraries

What are Shared Libraries?

What are Shared Libraries?

Like an archive library, a shared library contains object code. However, ld treats shared libraries quite differently from archive libraries. When linking an object file with a shared library, ld does not copy object code from the library into the a.out file; instead, the linker simply notes in the a.out file that the code calls a routine in the shared library. An a.out file that calls routines in a shared library is known as an incomplete executable.

The Dynamic Loader dld.sl

When an incomplete executable begins execution, the HP-UX dynamic loader (see dld.sl(5)) looks at the a.out file to see what libraries the a.out file needs during execution. In 32-bit mode, the startup code in crt0.o activates the dynamic loader. In 64-bit mode, the kernel activates the dynamic loader for a 64-bit a.out.The dynamic loader then loads and maps any required shared libraries into the process's address space — known as attaching the libraries. A program calls shared library routines indirectly through a linkage table that the dynamic loader fills in with the addresses of the routines. By default, the dynamic loader places the addresses of shared library routines in the linkage table as the routines are called — known as deferred binding. Immediate binding is also possible — that is, binding all required symbols in the shared library at program startup. In either case, any routines that are already loaded are shared.

Consequently, linking with shared libraries generally results in smaller a.out files than linking with archive libraries. Therefore, a clear benefit of using shared libraries is that it can reduce disk space and virtual memory requirements.

In prior releases, data defined by a shared library was copied into the program file at link time. All references to this data, both in the libraries and in the program file, referred to the copy in the executable file.

With the HP-UX 10.0 release, however, this data copying is eliminated. Data is accessed in the shared library itself. The code in the executable file references the shared library data indirectly through a linkage pointer, in the same way that a shared library would reference the data.

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HP 9000 specifications

The Kenwood HP 9000 is a cutting-edge home appliance designed for culinary enthusiasts seeking to elevate their cooking experience. This powerful kitchen machine stands out for its multi-functionality, combining the roles of a food processor, blender, and mixer into one sleek unit.

One of the flagship features of the Kenwood HP 9000 is its robust motor, which delivers exceptional performance across various tasks. With a powerful motor that operates at multiple speeds, users can tackle everything from kneading dough to finely chopping vegetables with ease. The variable speed control allows for precision, ensuring that every ingredient is processed to perfection according to individual preferences.

The HP 9000 comes equipped with a variety of attachments that enhance its versatility. Among these are a stainless-steel mixing bowl, a dough hook, a whisk, and multiple cutting blades. This extensive array of accessories means that users can whip up delightful pastries, create homemade pasta, or prepare smoothies with minimal hassle. Each attachment is designed for easy attachment and removal, making the transition between tasks seamless and efficient.

Another key characteristic of the Kenwood HP 9000 is its advanced safety features. The design incorporates mechanisms that prevent the machine from operating unless all components are securely in place. This not only gives users peace of mind while cooking but also ensures longevity for the appliance, reducing the risk of wear and tear over time.

In terms of design, the HP 9000 is both modern and aesthetically pleasing. Its ergonomic shape and compact size make it easy to store and use in various kitchen settings, while the high-quality materials used in its construction guarantee durability and longevity. The user interface is intuitive, with clearly labeled buttons that facilitate operation, ensuring that even novice cooks can navigate the machine effortlessly.

Additionally, the Kenwood HP 9000 features innovative technologies, such as an integrated digital timer and a pulse function for added control during food preparation. These features enhance cooking precision, allowing users to achieve consistent results every time.

In summary, the Kenwood HP 9000 is an exceptional kitchen appliance that combines power, versatility, and safety. With its advanced features and user-friendly design, it is an ideal choice for anyone looking to simplify their cooking process while achieving professional-level results. Whether you're whipping up a quick meal or tackling an elaborate recipe, the HP 9000 is a reliable companion that will inspire culinary creativity.