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Strings
In C, string constants (literals) are surrounded by double quotes ("), e.g. "Hello world!" and are compiled to an array of the specified char values with an additional null terminating character (0-valued) code to mark the end of the string.
String literals may not contain embedded newlines; this proscription somewhat simplifies parsing of the language. To include a newline in a string, the backslash escape \n may be used, as below.
Backslash escapes
If you wish to include a double quote inside the string, that can be done by escaping it with a backslash (\), for example, "This string contains \"double quotes\".". To insert a literal backslash, one must double it, e.g. "A backslash looks like this: \\".
Backslashes may be used to enter control characters, etc., into a string:
| Escape | Meaning |
|---|---|
| \\ | Literal backslash |
| \" | Double quote |
| \' | Single quote |
| \n | Newline (line feed) |
| \r | Carriage return |
| \b | Backspace |
| \t | Horizontal tab |
| \f | Form feed |
| \a | Alert (bell) |
| \v | Vertical tab |
| \? | Question mark (used to escape trigraphs) |
| %% | Percentage mark, printf format strings only (Note \% is non standard and is not always recognised) |
| \ooo | Character with octal value ooo |
| \xhh | Character with hexadecimal value hh |
