Standard C Library Functions ungetc(3C)
NAME
ungetc - push byte back into input stream
SYNOPSIS
#include
int ungetc(int c, FILE *stream);
DESCRIPTION
The ungetc() function pushes the byte specified by c (con-
verted to an unsigned char) back onto the input streampointed to by stream. The pushed-back bytes will be returned
by subsequent reads on that stream in the reverse order of their pushing. A successful intervening call (with thestream pointed to by stream) to a file-positioning function
( fseek(3C), fsetpos(3C) or rewind(3C)) discards anypushed-back bytes for the stream. The external storage
corresponding to the stream is unchanged.Four bytes of push-back are guaranteed. If ungetc() is
called too many times on the same stream without an inter-
vening read or file-positioning operation on that stream,
the operation may fail.If the value of c equals that of the macro EOF, the opera-
tion fails and the input stream is unchanged.A successful call to ungetc() clears the end-of-file indica-
tor for the stream. The value of the file-position indicator
for the stream after reading or discarding all pushed-back
bytes will be the same as it was before the bytes werepushed back. The file-position indicator is decremented by
each successful call to ungetc(); if its value was 0 before
a call, its value is indeterminate after the call.RETURN VALUES
Upon successful completion, ungetc() returns the byte pushed
back after conversion. Otherwise it returns EOF.ERRORS
No errors are defined.ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:SunOS 5.11 Last change: 10 Sep 2003 1
Standard C Library Functions ungetc(3C)
____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|_____________________________|
| Interface Stability | Committed ||_____________________________|_____________________________|
| MT-Level | MT-Safe |
|_____________________________|_____________________________|
| Standard | See standards(5). ||_____________________________|_____________________________|
SEE ALSO
read(2), Intro(3), __fsetlocking(3C), fseek(3C),
fsetpos(3C), getc(3C), setbuf(3C), stdio(3C), attributes(5), standards(5)SunOS 5.11 Last change: 10 Sep 2003 2