C Library

The ANSI C standard library includes a variety of utility functions defined in stdlib.h. The header file defines the types shown in table below: TypeDescription size_tThe integer type returned by the sizeof operator. wchar_tThe integer type used to represent wide characters. div_tThe structure type returned by div(); it has a quot and a rem member, both of type int. ldiv_tThe structure type returned by ldiv(); it has a quot and a rem member, both of type long. The header file … [Read more...] about C Library – <stdlib.h>

The Time library provides the data structures and functions required to retrieve the system time, perform time calculations, and output formatted strings that allow the time to be displayed in a variety of common formats. Time is stored as ticks since 1 Jan 1970, midnight, known as UTC. This value must be converted to be of use, either into a structure or formatted output. The time.h header file defines two macros. The first, also defined in many other header files, is NULL, representing the … [Read more...] about C Library – <time.h>

The string.h library defines the size_t type and the NULL macro for the null pointer. It provides several functions for analyzing and manipulating character strings and a few that deal with memory more generally. The table below lists the functions. PrototypeDescription void *memchr(const void *s, int c, size_t n);Searches for the first occurrence of c (converted to unsigned char) in the initial n characters of the object pointed to by s; returns a pointer to the first occurrence, NULL if … [Read more...] about C Library – <string.h>