NAME |LIBRARY |SYNOPSIS |DESCRIPTION |RETURN VALUE |ATTRIBUTES |STANDARDS |HISTORY |NOTES |SEE ALSO |COLOPHON | |
ungetwc(3) Library Functions Manualungetwc(3)ungetwc - push back a wide character onto a FILE stream
Standard C library (libc,-lc)
#include <wchar.h>wint_t ungetwc(wint_twc, FILE *stream);
Theungetwc() function is the wide-character equivalent of theungetc(3) function. It pushes back a wide character ontostream and returns it. Ifwc isWEOF, it returnsWEOF. Ifwc is an invalid wide character, it setserrno toEILSEQand returnsWEOF. Ifwc is a valid wide character, it is pushed back onto the stream and thus becomes available for future wide-character read operations. The file-position indicator is decremented by one or more. The end-of-file indicator is cleared. The backing storage of the file is not affected. Note:wc need not be the last wide-character read from the stream; it can be any other valid wide character. If the implementation supports multiple push-back operations in a row, the pushed-back wide characters will be read in reverse order; however, only one level of push-back is guaranteed.
Theungetwc() function returnswc when successful, orWEOFupon failure.
For an explanation of the terms used in this section, seeattributes(7). ┌──────────────────────────────────────┬───────────────┬─────────┐ │Interface│Attribute│Value│ ├──────────────────────────────────────┼───────────────┼─────────┤ │ungetwc() │ Thread safety │ MT-Safe │ └──────────────────────────────────────┴───────────────┴─────────┘
C11, POSIX.1-2008.
POSIX.1-2001, C99.
The behavior ofungetwc() depends on theLC_CTYPEcategory of the current locale.
fgetwc(3)
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