20 General utilities library [utilities]

20.20 Formatting [format]

20.20.2 Format string [format.string] Standard format specifiers [format.string.std]

Table 66: Meaning of type options for bool[tab:format.type.bool]
none, s
Copies textual representation, either true or false, to the output.
b, B, c, d, o, x, X
As specified in Table 64 for the value static_­cast<unsigned char>(value).