Ctype.h
Character Functions
| Function Name | Description | Return |
|---|---|---|
| isalpha | It tests the given character, whether it is an alphabet (A to Z or a to z). | Integer |
| islower | It test the given character, whether it is a lower case character(a to z) or not. | Integer |
| isupper | It test the given character, whether it is an upper case character (A to Z) | Integer |
| tolower | If the character is an uppercase character (A to Z), then it is converted to lowercase (a to z) character. | Integer |
| toupper | If the character is a lowercase character (a to z), then it is converted to uppercase (A to Z) character. | Integer |
Number Functions
| Function Name | Description | Return |
|---|---|---|
| isalnum | It test the given character, whether it is an alphabet (A to Z or a to z) or a digit (0 to 9) | Integer |
| isdigit | It test the given character, whether it is a digit (0 to 9). | Integer |
| isxdigit | It test the given character, whether it is a hexadecimal digit (0 to 9,A to F or a to f) | Integer |
Control Functions
| Function Name | Description | Return |
|---|---|---|
| isgraph | It test the given character, whether it is any printing character except for the space character (0x21 to 0x7E) | Integer |
| isprint | It test the given character, whether it is any printing character (0x20 to 0x7E) | Integer |
iscntrl | It test the given character, whether it is any control character (0x00 to 0x1F or 0x7F) | Integer |
| ispunct | It test the given character, whether it is any punctuation character (any printing character except for space character or isalnum) | Integer |
| isblank | It test the given character, whether it is a blank character (space and horizontal tab). | Integer |
| isspace | It test the given character, whether it is a white space character (space,tab,carriage return,new line,vertical tab,or formfeed) | Integer |