1) The file position indicator is incremented by fgetc() and decremented
by ungetc():
<http://www.opengroup.org/susv3/functions/fgetc.html>
+ "... the fgetc() function shall ... advance the associated file
+ position indicator for the stream ..."
+ <http://www.opengroup.org/susv3/functions/ungetc.html>
"The file-position indicator is decremented by each successful
call to ungetc()..."
- <http://www.opengroup.org/susv3/functions/ungetc.html>
- "... the fgetc() function shall ... advance the associated file
- position indicator for the stream ..."
2) <http://www.opengroup.org/susv3/functions/ungetc.html> says:
"The value of the file-position indicator for the stream after
reading or discarding all pushed-back bytes shall be the same