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UNGETC(3)	       FreeBSD Library Functions Manual		     UNGETC(3)

NAME
     ungetc -- un-get character	from input stream

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     #include <stdio.h>

     int
     ungetc(int	c, FILE	*stream);

DESCRIPTION
     The ungetc() function pushes the character	c (converted to	an unsigned
     char) back	onto the input stream pointed to by stream.  The pushed-back
     characters	will be	returned by subsequent reads on	the stream (in reverse
     order).  A	successful intervening call, using the same stream, to one of
     the file positioning functions (fseek(3), fsetpos(3), or rewind(3)) will
     discard the pushed	back characters.

     One character of push-back	is guaranteed, but as long as there is suffi-
     cient memory, an effectively infinite amount of pushback is allowed.

     If	a character is successfully pushed-back, the end-of-file indicator for
     the stream	is cleared.  The file-position indicator is decremented	by
     each successful call to ungetc(); if its value was	0 before a call, its
     value is unspecified after	the call.

RETURN VALUES
     The ungetc() function returns the character pushed-back after the conver-
     sion, or EOF if the operation fails.  If the value	of the argument	c
     character equals EOF, the operation will fail and the stream will remain
     unchanged.

SEE ALSO
     fseek(3), getc(3),	setvbuf(3), ungetwc(3)

STANDARDS
     The ungetc() function conforms to ISO/IEC 9899:1990 (``ISO	C90'').

FreeBSD	Ports 11.2		 June 4, 1993		    FreeBSD Ports 11.2

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | SEE ALSO | STANDARDS

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