The ANSI standard library provides many utility routines for doing common operations in C programs. The structures, types, macros, and functions of the standard library are declared in corresponding system header files. In order to have access to routines declared in these header files, the header files must be included in a source file via an include directive. This Appendix describes some of the more common and important applications oriented routines, but leaves out many others. The next section lists gives a brief description of these routines organized by category and header file. The following section is an alphabetic listing giving prototype statements and a detailed description.