C Programming Character Literals

Last modified by Microchip on 2023/11/10 10:59

Rules

  • Must be surrounded by single quotes (').
  • May include any single printable character (e.g. 'a').
  • May include any single non-printable character using escape sequences, also called diagraphs (e.g. '\0' for NUL).

Examples of Valid Character Literals

'a''T''\n''5''@'' ' (space)

Examples of Invalid Character Literals

'me''23''''

Because the single quote (') is used to delimit character literals, the single quote cannot by itself be a character literal. It must be specified using an escape sequence: '\''.

Although escape sequences look like two characters, the backslash (\) is treated specially in character and string literals. It signals that the character that follows is special. It either represents a non-printable character, as in the case of '\0' for NUL, or a character that cannot be used on its own in a character literal, such as the single quote or backslash themselves, which are represented as '\'' and '\\' respectively.