Routine |
Attributes |
Description |
isalnum |
reentrant |
Tests for an alphanumeric character |
isalpha |
reentrant |
Tests for an alphabetic character |
iscntrl |
reentrant |
Tests for a Control character |
isdigit |
reentrant |
Tests for a decimal digit |
isgraph |
reentrant |
Tests for a printable character with the exception of space |
islower |
reentrant |
Tests for a lowercase alphabetic character |
isprint |
reentrant |
Tests for a printable character |
ispunct |
reentrant |
Tests for a punctuation character |
isspace |
reentrant |
Tests for a whitespace character |
isupper |
reentrant |
Tests for an uppercase alphabetic character |
isxdigit |
reentrant |
Tests for a hexadecimal digit |
toascii |
reentrant |
Converts a character to an ASCII code |
toint |
reentrant |
Converts a hexadecimal digit to a decimal value |
tolower |
reentrant |
Tests a character and converts it to lowercase if it is uppercase |
_tolower |
reentrant |
Unconditionally converts a character to lowercase |
toupper |
reentrant |
Tests a character and converts it to uppercase if it is lowercase |
_toupper |
reentrant |
Unconditionally converts a character to uppercase |
The character conversion and classification routines allow you to test individual characters for a variety of attributes and convert characters to different formats.
The _tolower, _toupper, and toascii routines are implemented as macros. All other routines are implemented as functions. All macro definitions and function prototypes are found in the CTYPE.H include file.