ANSI-C Quoting

Character sequences of the form $’string’ are treated as a special kind of single quotes. The sequence expands to string, with backslash-escaped characters in string replaced as specified by the ANSI C standard. Backslash escape sequences, if present, are decoded as follows:

\a

alert (bell)

\b

backspace

\e

\E

an escape character (not ANSI C)

\f

form feed

\n

newline

\r

carriage return

\t

horizontal tab

\v

vertical tab

\\

backslash

\'

single quote

\"

double quote

\?

question mark

\nnn

the eight-bit character whose value is the octal value nnn (one to three octal digits)

\xHH

the eight-bit character whose value is the hexadecimal value HH (one or two hex digits)

\uHHHH

the Unicode (ISO/IEC 10646) character whose value is the hexadecimal value HHHH (one to four hex digits)

\UHHHHHHHH

the Unicode (ISO/IEC 10646) character whose value is the hexadecimal value HHHHHHHH (one to eight hex digits)

\cx

a control-x character

The expanded result is single-quoted, as if the dollar sign had not been present.