ANSI C Stdlib Library

The mikroC PRO for 8051 provides a set of standard ANSI C library functions of general utility.

Important :

Not all of the standard functions have been included.
The functions have been mostly implemented according to the ANSI C standard, but certain functions have been modified in order to facilitate 8051 programming. Be sure to skim through the description before using standard C functions.

Library Functions

abs
atof
atoi
atol
div
ldiv
uldiv
labs
max
min
rand
srand
xtoi

abs

Prototype	int abs(int a);
Description	Function returns the absolute (i.e. positive) value of `a`.
Example	result = abs(-12); // result = 12

atof

Prototype	double atof(char *s);
Description	Function converts the input string `s` into a double precision value and returns the value. Input string `s` should conform to the floating point literal format, with an optional whitespace at the beginning. The string will be processed one character at a time, until the function reaches a character which it doesn’t recognize (including a null character).
Example	doub = atof("-1.23"); // doub = -1.23

atoi

Prototype	int atoi(char *s);
Description	Function converts the input string `s` into an integer value and returns the value. The input string `s` should consist exclusively of decimal digits, with an optional whitespace and a sign at the beginning. The string will be processed one character at a time, until the function reaches a character which it doesn’t recognize (including a null character).
Example	result = atoi("32000"); // result = 32000

atol

Prototype	long atol(char *s);
Description	Function converts the input string `s` into a long integer value and returns the value. The input string `s` should consist exclusively of decimal digits, with an optional whitespace and a sign at the beginning. The string will be processed one character at a time, until the function reaches a character which it doesn’t recognize (including a null character).
Example	result = atol("-32560"); // result = -32560

div

Prototype	div_t div(int number, int denom);
Description	Function computes the result of division of the numerator `number` by the denominator `denom`; the function returns a structure of type `div_t` comprising quotient (`quot`) and remainder (`rem`), see Div Structures.
Example	dt = div(1234,100);

ldiv

Prototype

Prototype	ldiv_t ldiv(long number, long denom);
Description	Function is similar to the div function, except that the arguments and result structure members all have type `long`. Function computes the result of division of the numerator `number` by the denominator `denom`; the function returns a structure of type `ldiv_t` comprising quotient (`quot`) and remainder (`rem`), see Div Structures.
Example	dl = ldiv(-123456, 1000);

ldiv_t ldiv(long number, long denom);

Description

Function is similar to the div function, except that the arguments and result structure members all have type long.

Function computes the result of division of the numerator number by the denominator denom; the function returns a structure of type ldiv_t comprising quotient (quot) and remainder (rem), see Div Structures.

Example

dl = ldiv(-123456, 1000);

uldiv

Prototype

Prototype	uldiv_t uldiv(unsigned long number, unsigned long denom);
Description	Function is similar to the div function, except that the arguments and result structure members all have type `unsigned long`. Function computes the result of division of the numerator `number` by the denominator `denom`; the function returns a structure of type `uldiv_t` comprising quotient (`quot`) and remainder (`rem`), see Div Structures.
Example	dul = uldiv(123456,1000);

uldiv_t uldiv(unsigned long number, unsigned long denom);

Description

Function is similar to the div function, except that the arguments and result structure members all have type unsigned long.

Function computes the result of division of the numerator number by the denominator denom; the function returns a structure of type uldiv_t comprising quotient (quot) and remainder (rem), see Div Structures.

Example

dul = uldiv(123456,1000);

labs

Prototype	long labs(long x);
Description	Function returns the absolute (i.e. positive) value of long integer `x`.
Example	result = labs(-2147483647);

max

Prototype	int max(int a, int b);
Description	Function returns greater of the two integers, `a` and `b`.
Example	result = max(123,67); // function returns 123

min

Prototype	int min(int a, int b);
Description	Function returns lower of the two integers, `a` and `b`.
Example	result = min(123,67); // function returns 67

rand

Prototype	int rand();
Description	Function returns a sequence of pseudo-random numbers between 0 and 32767. The function will always produce the same sequence of numbers unless srand is called to seed the start point.
Example	while(1) result = rand() ;

srand

Prototype	void srand(unsigned x);
Description	Function uses `x` as a starting point for a new sequence of pseudo-random numbers to be returned by subsequent calls to rand. No values are returned by this function.
Example	srand(9);

xtoi

Prototype	unsigned xtoi(char *s);
Description	Function converts the input string `s` consisting of hexadecimal digits into an integer value. The input parameter `s` should consist exclusively of hexadecimal digits, with an optional whitespace and a sign at the beginning. The string will be processed one character at a time, until the function reaches a character which it doesn’t recognize (including a null character).
Example	result = xtoi("1FF"); // result = 511

Div Structures

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 typedef struct divstruct {
             int quot;
             int rem;
 } div_t;


 typedef struct ldivstruct {
             long quot;
             long rem;
 } ldiv_t;


 typedef struct uldivstruct {
             unsigned long quot;
             unsigned long rem;
 } uldiv_t;

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