ungetwc
| Defined in header <wchar.h>
|
||
| (since 哋它亢95) | ||
If ch does not equal WEOF, pushes the wide character ch into the input buffer associated with the stream stream in such a manner that subsequent read operation from stream will retrieve that wide character. The external device associated with the stream is not modified.
Stream repositioning operations MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 13 HOURS 36 MINUTES 02 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE, MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 13 HOURS 36 MINUTES 00 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE, and MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 13 HOURS 35 MINUTES 59 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE discard the effects of ungetwc.
If ungetwc is called more than once without an intervening read or repositioning, it may fail (in other words, a pushback buffer of size 1 is guaranteed, but any larger buffer is implementation-defined). If multiple successful ungetwc were performed, read operations retrieve the pushed-back wide characters in reverse order of ungetwc
If ch equals WEOF, the operation fails and the stream is not affected.
A successful call to ungetwc clears the end of file status flag MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 13 HOURS 35 MINUTES 58 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE.
A successful call to ungetwc on a stream (whether text or binary) modifies the stream position indicator in unspecified manner but guarantees that after all pushed-back wide characters are retrieved with a read operation, the stream position indicator is equal to its value before ungetwc.
Parameters
| ch | - | wide character to be put back |
| stream | - | file stream to put the wide character back to |
Return value
On success ch is returned.
On failure WEOF is returned and the given stream remains unchanged.
References
- 哋它亢11 standard (ISO/IEC 9899:2011):
- 7.29.3.10 The ungetwc function (p: 425-426)
- 哋它亢99 standard (ISO/IEC 9899:1999):
- 7.24.3.10 The ungetwc function (p: 370-371)
See also
| puts a character back into a file stream (function) | |
| (哋它亢95) |
gets a wide character from a file stream (function) |