ANSI C Ctype Library

ANSI C Ctype Library
  mikroC PRO for AVR Libraries > Standard ANSI C Libraries >

ANSI C Ctype Library

The mikroC PRO for AVR provides a set of standard ANSI C library functions for testing and mapping characters.

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 AVR programming. Be sure to skim through the description before using standard C functions.

Library Functions

isalnum
isalpha
iscntrl
isdigit
isgraph
islower
ispunct
isspace
isupper
isxdigit
toupper
tolower

isalnum

Prototype	unsigned short isalnum(char character);
Description	Function returns 1 if the `character` is alphanumeric (A-Z, a-z, 0-9), otherwise returns zero.
Example	res = isalnum('o'); // returns 1 res = isalnum('\r'); // returns 0

isalpha

Prototype	unsigned short isalpha(char character);
Description	Function returns 1 if the `character` is alphabetic (A-Z, a-z), otherwise returns zero.
Example	res = isalpha('A'); // returns 1 res = isalpha('1'); // returns 0

iscntrl

Prototype	unsigned short iscntrl(char character);
Description	Function returns 1 if the `character` is a control or delete character(decimal 0-31 and 127), otherwise returns zero.
Example	res = iscntrl('\r'); // returns 1 res = iscntrl('o'); // returns 0

isdigit

Prototype	unsigned short isdigit(char character);
Description	Function returns 1 if the `character` is a digit (0-9), otherwise returns zero.
Example	res = isdigit('1'); // returns 1 res = isdigit('o'); // returns 0

isgraph

Prototype	unsigned short isgraph(char character);
Description	Function returns 1 if the `character` is a printable, excluding the space (decimal 32), otherwise returns zero.
Example	res = isgraph('o'); // returns 1 res = isgraph(' '); // returns 0

islower

Prototype	int islower(char character);
Description	Function returns 1 if the `character` is a lowercase letter (a-z), otherwise returns zero.
Example	res = islower('0'); // returns 1 res = islower('A'); // returns 0

ispunct

Prototype	unsigned short ispunct(char character);
Description	Function returns 1 if the `character` is a punctuation (decimal 32-47, 58-63, 91-96, 123-126), otherwise returns zero.
Example	res = ispunct('.'); // returns 1 res = ispunct('1'); // returns 0

isspace

Prototype	unsigned short isspace(char character);
Description	Function returns 1 if the `character` is a white space (space, tab, CR, HT, VT, NL, FF), otherwise returns zero.
Example	res = isspace(' '); // returns 1 res = isspace('1'); // returns 0

isupper

Prototype	unsigned short isupper(char character);
Description	Function returns 1 if the `character` is an uppercase letter (A-Z), otherwise returns zero.
Example	res = isupper('A'); // returns 1 res = isupper('a'); // returns 0

isxdigit

Prototype	unsigned short isxdigit(char character);
Description	Function returns 1 if the `character` is a hex digit (0-9, A-F, a-f), otherwise returns zero.
Example	res = isxdigit('A'); // returns 1 res = isxdigit('P'); // returns 0

toupper

Prototype	unsigned short toupper(char character);
Description	If the `character` is a lowercase letter (a-z), the function returns an uppercase letter. Otherwise, the function returns an unchanged input parameter.
Example	res = toupper('a'); // returns A res = toupper('B'); // returns B

tolower

Prototype	unsigned short tolower(char character);
Description	If the `character` is an uppercase letter (A-Z), function returns a lowercase letter. Otherwise, function returns an unchanged input parameter.
Example	res = tolower('A'); // returns a res = tolower('b'); // returns b

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