As per the C standard, calling ungetc() with the character parameter
equal to EOF causes it to fail, returning EOF.
Signed-off-by: Ian Abbott <abbotti@xxxxxxxxx>
---
v2: Correct English grammar usage for "otherwise".
v3: Move detail of EOF special case to the end of the paragraph to give
it less prominence, as suggested by Alex.
---
man3/fgetc.3 | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/man3/fgetc.3 b/man3/fgetc.3
index 75dcaeaf6..a15d73b15 100644
--- a/man3/fgetc.3
+++ b/man3/fgetc.3
@@ -62,7 +62,7 @@ A terminating null byte (\[aq]\e0\[aq])
is stored after the last character in the buffer.
.PP
.BR ungetc ()
-pushes
+normally pushes
.I c
back to
.IR stream ,
@@ -71,6 +71,13 @@ cast to
where it is available for subsequent read operations.
Pushed-back characters
will be returned in reverse order; only one pushback is guaranteed.
+If the value of
+.I c
+equals that of the macro
+.BR EOF ,
+nothing is pushed back to
+.I stream
+and an error is returned.
.PP
Calls to the functions described here can be mixed with each other and with
calls to other input functions from the
--
2.39.2
