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34 .\" @(#)ungetc.3 8.1 (Berkeley) 6/4/93
41 .Nd un-get wide character from input stream
48 .Fn ungetwc "wint_t wc" "FILE *stream"
52 function pushes the wide character
54 (converted to an wchar_t)
55 back onto the input stream pointed to by
57 The pushed-backed wide characters will be returned by subsequent reads on the
58 stream (in reverse order).
59 A successful intervening call, using the same stream, to one of the file
65 will discard the pushed back wide characters.
67 One wide character of push-back is guaranteed,
68 but as long as there is
69 sufficient memory, an effectively infinite amount of pushback is allowed.
71 If a character is successfully pushed-back,
72 the end-of-file indicator for the stream is cleared.
78 the wide character pushed-back after the conversion, or
80 if the operation fails.
81 If the value of the argument
85 the operation will fail and the stream will remain unchanged.
95 The current implementation uses a fixed sized ungetwc-buffer.