1.\" $NetBSD: ferror.3,v 1.5 1995/02/02 01:15:35 jtc Exp $ 2.\" 3.\" Copyright (c) 1990, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" This code is derived from software contributed to Berkeley by 7.\" Chris Torek and the American National Standards Committee X3, 8.\" on Information Processing Systems. 9.\" 10.\" Redistribution and use in source and binary forms, with or without 11.\" modification, are permitted provided that the following conditions 12.\" are met: 13.\" 1. Redistributions of source code must retain the above copyright 14.\" notice, this list of conditions and the following disclaimer. 15.\" 2. Redistributions in binary form must reproduce the above copyright 16.\" notice, this list of conditions and the following disclaimer in the 17.\" documentation and/or other materials provided with the distribution. 18.\" 3. All advertising materials mentioning features or use of this software 19.\" must display the following acknowledgement: 20.\" This product includes software developed by the University of 21.\" California, Berkeley and its contributors. 22.\" 4. Neither the name of the University nor the names of its contributors 23.\" may be used to endorse or promote products derived from this software 24.\" without specific prior written permission. 25.\" 26.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36.\" SUCH DAMAGE. 37.\" 38.\" @(#)ferror.3 8.2 (Berkeley) 4/19/94 39.\" 40.Dd April 19, 1994 41.Dt FERROR 3 42.Os 43.Sh NAME 44.Nm clearerr , 45.Nm feof , 46.Nm ferror , 47.Nm fileno 48.Nd check and reset stream status 49.Sh SYNOPSIS 50.Fd #include <stdio.h> 51.Ft void 52.Fn clearerr "FILE *stream" 53.Ft int 54.Fn feof "FILE *stream" 55.Ft int 56.Fn ferror "FILE *stream" 57.Ft int 58.Fn fileno "FILE *stream" 59.Sh DESCRIPTION 60The function 61.Fn clearerr 62clears the end-of-file and error indicators for the stream pointed 63to by 64.Fa stream . 65.Pp 66The function 67.Fn feof 68tests the end-of-file indicator for the stream pointed to by 69.Fa stream , 70returning non-zero if it is set. 71The end-of-file indicator can only be cleared by the function 72.Fn clearerr . 73.Pp 74The function 75.Fn ferror 76tests the error indicator for the stream pointed to by 77.Fa stream , 78returning non-zero if it is set. 79The error indicator can only be reset by the 80.Fn clearerr 81function. 82.Pp 83The function 84.Fn fileno 85examines the argument 86.Fa stream 87and returns its integer descriptor. 88.Sh ERRORS 89These functions should not fail and do not set the external 90variable 91.Va errno . 92.Sh SEE ALSO 93.Xr open 2 , 94.Xr stdio 3 95.Sh STANDARDS 96The functions 97.Fn clearerr , 98.Fn feof , 99and 100.Fn ferror 101conform to 102.St -ansiC . 103The function 104.Fn fileno 105conforms to 106.St -p1003.1-90 . 107