ungetc(3S)          (C Programming Language Utilities)           ungetc(3S)


   NAME
         ungetc - push character back onto input stream

   SYNOPSIS
         #include <stdio.h>

         int ungetc (int c, FILE *stream);

   DESCRIPTION
         ungetc inserts the character specified by c (converted to an unsigned
         char) into the buffer associated with an input stream [see intro(3)].
         That character, c, will be returned by the next getc(3S) call on that
         stream.  ungetc returns c, and leaves the file corresponding to
         stream unchanged.  A successful call to ungetc clears the EOF
         indicator for stream.

         Four bytes of pushback are guaranteed.

         The value of the file position indicator for stream after reading or
         discarding all pushed-back characters will be the same as it was
         before the characters were pushed back.

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

         fseek, rewind [both described on fseek(3S)], and fsetpos erase the
         memory of inserted characters for the stream on which they are
         applied.

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

   DIAGNOSTICS
         ungetc returns EOF if it cannot insert the character.




















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