Link-Editing

Link-editing takes a variety of input files, from cc(1), as(1) or ld(1), and concatenates and interprets the data within these input files to form a single output file. Although the link-editor provides numerous options, the output file that it produces is one of four basic types:

• Relocatable object - A concatenation of input relocatable objects that can be used in subsequent link-edit phases.

• Static executable - A concatenation of input relocatable objects that has all symbolic references bound to the executable, and thus represents a ready-to-run process.

• Dynamic executable - A concatenation of input relocatable objects that requires intervention by the runtime linker to produce a runnable process. A dynamic executable might still need symbolic references bound at runtime, and can have one or more dependencies in the form of shared objects.

• Shared object - A concatenation of input relocatable objects that provides services that might be bound to a dynamic executable at runtime. The shared object can have dependencies on other shared objects.

These output files, and the key link-editor options used to create them, are shown in Figure 1-1.

Dynamic executables and shared objects are often referred to jointly as dynamic objects and are the main focus of this document.

Figure 1-1 Static or Dynamic Link-Editing