'\" t
.\" Copyright (C) 2001 Andries Brouwer <aeb@cwi.nl>.
.\"
.\" SPDX-License-Identifier: Linux-man-pages-copyleft
.\"
.TH fpurge 3 2022-12-15 "Linux man-pages 6.03"
.SH NAME
fpurge, __fpurge \- purge a stream
.SH LIBRARY
Standard C library
.RI ( libc ", " \-lc )
.SH SYNOPSIS
.nf
/* unsupported */
.B #include <stdio.h>
.PP
.BI "int fpurge(FILE *" stream );
.PP
/* supported */
.B #include <stdio.h>
.B #include <stdio_ext.h>
.PP
.BI "void  __fpurge(FILE *" stream );
.fi
.SH DESCRIPTION
The function
.BR fpurge ()
clears the buffers of the given 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
.BR getc (3);
this includes any text pushed back via
.BR ungetc (3).
See also
.BR fflush (3).
.PP
The function
.BR __fpurge ()
does precisely the same, but without returning a value.
.SH RETURN VALUE
Upon successful completion
.BR fpurge ()
returns 0.
On error, it returns \-1 and sets
.I errno
to indicate the error.
.SH ERRORS
.TP
.B EBADF
.I stream
is not an open stream.
.SH ATTRIBUTES
For an explanation of the terms used in this section, see
.BR attributes (7).
.ad l
.nh
.TS
allbox;
lbx lb lb
l l l.
Interface	Attribute	Value
T{
.BR __fpurge ()
T}	Thread safety	MT-Safe race:stream
.TE
.hy
.ad
.sp 1
.SH STANDARDS
These functions are nonstandard and not portable.
The function
.BR fpurge ()
was introduced in 4.4BSD and is not available under Linux.
The function
.BR __fpurge ()
was introduced in Solaris, and is present in glibc 2.1.95 and later.
.SH NOTES
Usually it is a mistake to want to discard input buffers.
.SH SEE ALSO
.\" .BR fclean (3),
.BR fflush (3),
.BR setbuf (3),
.BR stdio_ext (3)