.\"	$OpenBSD: fflush.3,v 1.12 2015/11/04 21:30:13 tedu Exp $
.\"
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.\" This code is derived from software contributed to Berkeley by
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.Dd $Mdocdate: November 4 2015 $
.Dt fpurge 3bsd
.Os
.Sh NAME
.Nm fpurge
.Nd flush a stream
.Sh LIBRARY
.ds str-Lb-libbsd Utility functions from BSD systems (libbsd, \-lbsd)
.ds doc-str-Lb-libbsd \*[str-Lb-libbsd]
.Lb libbsd
.Sh SYNOPSIS
.In stdio.h
(See
.Xr libbsd 7
for include usage.)
.Ft int
.Fn fpurge "FILE *stream"
.Sh DESCRIPTION
The function
.Fn fpurge
erases any input or output buffered in the given
.Fa stream .
For output streams this discards any unwritten output.
For input streams this discards any input read from the underlying object
but not yet obtained via
.Xr getc 3 ;
this includes any text pushed back via
.Xr ungetc 3 .
.Sh RETURN VALUES
Upon successful completion 0 is returned.
Otherwise,
.Dv EOF
is returned and the global variable
.Va errno
is set to indicate the error.
.Sh ERRORS
.Bl -tag -width Er
.It Bq Er EBADF
.Fa stream
is not an open stream.
.El
.Sh SEE ALSO
.Xr fclose 3 ,
.Xr fopen 3 ,
.Xr setvbuf 3
.Sh HISTORY
The
.Fn fpurge
function first appeared in
.Bx 4.4 Lite .