вывод символов (character output)
Ошибки (Error)
For the conditions under which fwprintf() and wprintf() fail and
may fail, refer to fputwc(3p).
In addition, all forms of fwprintf() shall fail if:
EILSEQ A wide-character code that does not correspond to a valid
character has been detected.
In addition, fwprintf() and wprintf() may fail if:
ENOMEM Insufficient storage space is available.
The swprintf() shall fail if:
EOVERFLOW
The value of n is greater than {INT_MAX} or the number of
bytes needed to hold the output excluding the terminating
null is greater than {INT_MAX}.
The following sections are informative.
