Replacement Functions

Some functions have extremely limited implementations on different platforms. Other functions are tedious to use correctly; for example, proper use of malloc calls for the return value to be checked and appropriate action taken if memory has been exhausted. A group of ‘replacement functions’ is available in libiberty to address these issues for some of the most commonly used subroutines.

All of these functions are declared in the libiberty.h header file. Many of the implementations will use preprocessor macros set by GNU Autoconf, if you decide to make use of that program. Some of these functions may call one another.

Memory Allocation

The functions beginning with the letter x are wrappers around standard functions; the functions provided by the system environment are called and their results checked before the results are passed back to client code. If the standard functions fail, these wrappers will terminate the program. Thus, these versions can be used with impunity.

Exit Handlers

The existence and implementation of the atexit routine varies amongst the flavors of Unix. libiberty provides an unvarying dependable implementation via xatexit and xexit.

Error Reporting

These are a set of routines to facilitate programming with the system errno interface. The libiberty source file strerror.c contains a good deal of documentation for these functions.