Creating and Using Libraries

Creating Shared Libraries

You may be surprised to find that a shared library exports many more symbols than necessary for code that uses the library. These extra symbols add to the size of the library's symbol table and can even degrade performance (since the dynamic loader has to search a larger-than-necessary number of symbols).

One possible way to improve shared library performance is to export only those symbols that need exporting from a library. To control which symbols are exported, use either the +e or the -hoption to the ld command. When +e options are specified, the linker exports only those symbols specified by +e options. The -hoption causes the linker to hide the specified symbols. (For details on using these options, see “Hiding Symbols with -h” on page 81 and “Exporting Symbols with +e” on page 79.)

As an example, suppose you've created a shared library that defines the procedures init_prog and quit_prog and the global variable prog_state. To ensure that only these symbols are exported from the library, specify these options when creating the library:

+e init_prog +e quit_prog +e prog_state

If you have to export many symbols, you may find it convenient to use the -cfile option, which allows you to specify linker options in file. For instance, you could specify the above options in a file named export_opts as:

+e init_prog +e quit_prog +e prog_state

Then you would specify the following option on the linker command line:

-c export_opts

(For details on the -coption, see “Passing Linker Options in a file with -c” on page 86.)

Placing Frequently-Called Routines Together

When the linker creates a shared library, it places the PIC object modules into the library in the order in which they are specified on the linker command line. The order in which the modules appear can greatly affect performance. For instance, consider the following modules:

a.o

Calls routines in c.o heavily, and its routines are

 

called frequently by c.o.

146

Chapter 5

Page 145 Page 147
Page 146
Image 146
Kenwood HP 9000 manual Placing Frequently-Called Routines Together, 146
Page 145 Page 147

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.
Top Page Image Contents