ungetwc()

push wide character back onto input stream 

Function


SYNOPSIS

#include <stdio.h>

#include <wchar.t>

wint_t ungetwc(wchar_t wc, FILE *stream);


DESCRIPTION

The ungetwc() function pushes the wide character wc back onto the input stream pointed to by stream. If stream is open in text mode, then the multibyte form of wc is pushed. The end-of-file indicator for stream is cleared, and subsequent reads will get any pushed back bytes in the reverse order that they were pushed. No actual writes, however, are performed to the file or other underlying storage of stream.

A successful call to a file-positioning function for stream, such as fsetpos() or rewind(), discards all pushed back characters of the stream.

The pushback buffer is limited. Repeated calls to ungetwc() with no intervening read or file positioning operations fail.


PARAMETERS

wc 

Is the wide character to push back onto stream.

stream 

Points to the input stream.


RETURN VALUES

If successful, the ungetwc() function returns the wide character that it pushed back. On failure, ungetwc() returns WEOF; if the failure is the result of an inability to translate wc into multibyte form, errno is set to EILSEQ.


CONFORMANCE

ANSI/ISO 9899-1990/AM 1-1995.


MULTITHREAD SAFETY LEVEL

MT-Safe.


PORTING ISSUES

None.


AVAILABILITY

PTC MKS Toolkit for Professional Developers
PTC MKS Toolkit for Professional Developers 64-Bit Edition
PTC MKS Toolkit for Enterprise Developers
PTC MKS Toolkit for Enterprise Developers 64-Bit Edition


SEE ALSO

Functions:
fputwc(), fsetpos(), rewind(), ungetc()


PTC MKS Toolkit 10.2 Documentation Build 28.