1.\" Copyright (c) 1990, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" Chris Torek and the American National Standards Committee X3, 6.\" on Information Processing Systems. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above copyright 14.\" notice, this list of conditions and the following disclaimer in the 15.\" documentation and/or other materials provided with the distribution. 16.\" 3. All advertising materials mentioning features or use of this software 17.\" must display the following acknowledgement: 18.\" This product includes software developed by the University of 19.\" California, Berkeley and its contributors. 20.\" 4. Neither the name of the University nor the names of its contributors 21.\" may be used to endorse or promote products derived from this software 22.\" without specific prior written permission. 23.\" 24.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34.\" SUCH DAMAGE. 35.\" 36.\" @(#)ferror.3 8.2 (Berkeley) 4/19/94 37.\" $FreeBSD$ 38.\" 39.Dd April 19, 1994 40.Dt FERROR 3 41.Os 42.Sh NAME 43.Nm clearerr , 44.Nm feof , 45.Nm ferror , 46.Nm fileno 47.Nd check and reset stream status 48.Sh SYNOPSIS 49.Fd #include <stdio.h> 50.Ft void 51.Fn clearerr "FILE *stream" 52.Ft int 53.Fn feof "FILE *stream" 54.Ft int 55.Fn ferror "FILE *stream" 56.Ft int 57.Fn fileno "FILE *stream" 58.Sh DESCRIPTION 59The function 60.Fn clearerr 61clears the end-of-file and error indicators for the stream pointed 62to by 63.Fa stream . 64.Pp 65The function 66.Fn feof 67tests the end-of-file indicator for the stream pointed to by 68.Fa stream , 69returning non-zero if it is set. 70The end-of-file indicator can only be cleared by the function 71.Fn clearerr . 72.Pp 73The function 74.Fn ferror 75tests the error indicator for the stream pointed to by 76.Fa stream , 77returning non-zero if it is set. 78The error indicator can only be reset by the 79.Fn clearerr 80function. 81.Pp 82The function 83.Fn fileno 84examines the argument 85.Fa stream 86and returns its integer descriptor. 87.Sh ERRORS 88These functions should not fail and do not set the external 89variable 90.Va errno . 91.Sh SEE ALSO 92.Xr open 2 , 93.Xr stdio 3 94.Sh STANDARDS 95The functions 96.Fn clearerr , 97.Fn feof , 98and 99.Fn ferror 100conform to 101.St -ansiC . 102