UNGETC(3S)           INTERACTIVE UNIX System           UNGETC(3S)



          NAME
               ungetc - push character back into input stream

          SYNOPSIS
               #include <stdio.h>

               int ungetc (c, stream)
               int c;
               FILE *stream;

          DESCRIPTION
               The ungetc function inserts the character c into the buffer
               associated with an input stream.  That character, c, will be
               returned by the next getc(3S) call on that stream.  The
               ungetc function returns c, and leaves the file stream
               unchanged.

               One character of pushback is guaranteed, provided something
               has already been read from the stream and the stream is
               actually buffered.

               If c equals EOF, ungetc does nothing to the buffer and
               returns EOF.

               The fseek(3S) function erases all memory of inserted charac-
               ters.

          SEE ALSO
               fseek(3S), getc(3S), setbuf(3S), stdio(3S).

          DIAGNOSTICS
               ungetc returns EOF if it cannot insert the character.

          BUGS
               When stream is stdin, one character may be pushed back onto
               the buffer without a previous read statement.



















          Rev. C Software Development Set                            Page 1