Utility Functions - C++ Tutorial

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Cpp

Topic

What are Utility functions in C++?

Explanation

The standard function has several utility functions for number of conversions, variable-length, argument processing, sorting and searching, and random number generation. To use these function the header <cstdlib> is required.

This header defines the types "div_t", "ldiv_t", "size_t". Following table lists the macros supported by <cstdlib> header.

Following table lists macros supported by utility functions of C++ Standard function Library.

EXIT_SUCCESS

Macro	Description
MB_CUR_MAX	Maximumlength in bytes of a multibyte character.
NULL	A null pointer.
RAND_MAX	Maximum value returned by the rand() function.
EXIT_FAILURE	Value retruned to calling process if program is terminated unsuccessfully.
Value retruned to calling process if program is terminated successfully.

The following table lists the important utility functions of C++ Standard Function Library.

Functions	Description
abort	Terminates the program abnormally.
abs	Returns the absolute value of the number.
atof	Converts a string into a double value.
atoi	Converts a string into a integer value.
atol	Converts a string into a long value.
bsearch	Performs a binary search on an array.
div	Returns the numerator, denominator of an integer value and quotient, remainder for a long value.
exit	Causes normal and immediate termination of a program.
getenv	Returns a pointer to the environmental variable for the given argument.
qsort	Function is used to quicksort an array.
rand	Generates a random number.
srand	Initializes a random number generation.

Utility Functions in C++