2.1 Supplemental Functions

Certain operating systems do not provide functions which have since become standardized, or at least common. For example, the Single Unix Specification Version 2 requires that the basename function be provided, but an OS which predates that specification might not have this function. This should not prevent well-written code from running on such a system.

Similarly, some functions exist only among a particular “flavor” or “family” of operating systems. As an example, the bzero function is often not present on systems outside the BSD-derived family of systems.

Many such functions are provided in libiberty. They are quickly listed here with little description, as systems which lack them become less and less common. Each function foo is implemented in foo.c but not declared in any libiberty header file; more comments and caveats for each function's implementation are often available in the source file. Generally, the function can simply be declared as extern.