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Escape sequences

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Escape sequences are used to define certain special characters within string literals.

The following escape sequences are available:

Escape
sequence
Description Representation
\' single quote byte 0x27
\" double quote byte 0x22
\? question mark byte 0x3f
\\ backslash byte 0x5c
\0 null character byte 0x00
\a audible bell byte 0x07
\b backspace byte 0x08
\f form feed - new page byte 0x0c
\n line feed - new line byte 0x0a
\r carriage return byte 0x0d
\t horizontal tab byte 0x09
\v vertical tab byte 0x0b
\nnn arbitrary octal value byte nnn
\xnn arbitrary hexadecimal value byte nn
\unnnn arbitrary Unicode value.
May result in several characters.
code point U+nnnn
\Unnnnnnnn arbitrary Unicode value.
May result in several characters.
code point U+nnnnnnnn

Notes

The new-line character \n has special meaning when used in text mode I/O, it is converted to the OS-specific newline byte or byte sequence.

Octal escape sequences have a limit of three octal digits, but terminate at the first character that is not a valid octal digit if encountered sooner.

Hexadecimal escape sequences have no length limit and terminate at the first character that is not a valid hexadecimal digit. If the value represented by a single hexadecimal escape sequence does not fit the range of values represented by the character type used in this string literal (char, char16_t, char32_t, or wchar_t), the result is unspecified.

A universal character name in a narrow string literal may map to more than one char due to multibyte encoding.

The question mark escape sequence \? is used to prevent trigraphs from being interpreted inside string literals: a string such as "??/" is compiled as "\", but if the second question mark is escaped, as in "?\?/", it becomes "??/"

Example

#include <iostream>
 
int main()
{
    std::printf("This\nis\na\ntest\n\nShe said, \"How are you?\"\n");
}

Output:

This
is
a
test
 
She said, "How are you?"

See also