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UNGETWC(3)            DragonFly Library Functions Manual            UNGETWC(3)


ungetwc, ungetwc_l -- un-get wide character from input stream


Standard C Library (libc, -lc)


#include <stdio.h> #include <wchar.h> wint_t ungetwc(wint_t wc, FILE *stream); #include <xlocale.h> wint_t ungetwc_l(wint_t wc, FILE *stream, locale_t locale);


The ungetwc() and ungetwc_l() functions push the wide character wc (converted to an wchar_t) back onto the input stream pointed to by stream. The pushed-backed wide characters will be returned by subsequent reads on the stream (in reverse order). A successful intervening call, using the same stream, to one of the file positioning functions fseek(3), fsetpos(3), or rewind(3) will discard the pushed back wide characters. One wide character of push-back is guaranteed, but as long as there is sufficient memory, an effectively infinite amount of pushback is allowed. If a character is successfully pushed-back, the end-of-file indicator for the stream is cleared. The ungetwc_l() function takes an explicit locale argument, whereas the ungetwc() function uses the current global or per-thread locale.


The ungetwc() and ungetwc_l() functions return the wide character pushed- back after the conversion, or WEOF if the operation fails. If the value of the argument c character equals WEOF, the operation will fail and the stream will remain unchanged.


fseek(3), getwc(3), xlocale(3)


The ungetwc() function conforms to ISO/IEC 9899:1999 (``ISO C99''). DragonFly 3.7 December 26, 2013 DragonFly 3.7

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