1.\" $NetBSD: fhopen.2,v 1.12 2004/05/13 10:20:58 wiz Exp $ 2.\" 3.\" Copyright (c) 1999 National Aeronautics & Space Administration 4.\" All rights reserved. 5.\" 6.\" This software was written by William Studenmund of the 7.\" Numerical Aerospace Simulation Facility, NASA Ames Research Center. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 3. Neither the name of the National Aeronautics & Space Administration 18.\" nor the names of its contributors may be used to endorse or promote 19.\" products derived from this software without specific prior written 20.\" permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE NATIONAL AERONAUTICS & SPACE ADMINISTRATION 23.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 24.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 25.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE ADMINISTRATION OR CONTRIB- 26.\" UTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 27.\" OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 28.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 29.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 30.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 31.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 32.\" POSSIBILITY OF SUCH DAMAGE. 33.\"/ 34.Dd April 14, 2004 35.Dt FHOPEN 2 36.Os 37.Sh NAME 38.Nm fhopen , 39.Nm fhstat , 40.Nm fhstatvfs 41.Nd access file via file handle 42.Sh LIBRARY 43.Lb libc 44.Sh SYNOPSIS 45.In sys/types.h 46.Ft int 47.Fn fhopen "const fhandle_t *fhp" "int flags" 48.In sys/stat.h 49.Ft int 50.Fn fhstat "const fhandle_t *fhp" "struct stat *sb" 51.In sys/statvfs.h 52.Ft int 53.Fn fhstatvfs "const fhandle_t *fhp" "struct statvfs *buf" 54.Ft int 55.Fn fhstatvfs1 "const fhandle_t *fhp" "struct statvfs *buf" "int flags" 56.Sh DESCRIPTION 57These functions provide a means to access a file given the file handle 58.Fa fhp . 59As this method bypasses directory access restrictions, these calls are 60restricted to the superuser. 61.Pp 62.Fn fhopen 63opens the file referenced by 64.Fa fhp 65for reading and/or writing as specified by the argument 66.Fa flags 67and returns the file descriptor to the calling process. 68The 69.Fa flags 70are specified by 71.Em or Ns 'ing 72together the flags used for the 73.Xr open 2 74call. 75All said flags are valid except for 76.Dv O_CREAT . 77.Pp 78.Fn fhstat , 79.Fn fhstatvfs , 80and 81.Fn fhstatvfs1 82provide the functionality of the 83.Xr fstat 2 , 84.Xr fstatvfs 2 , 85and 86.Xr fstatvfs1 2 87calls except that they return information for the file referred to by 88.Fa fhp 89rather than an open file. 90.Sh RETURN VALUES 91Upon successful completion, 92.Fn fhopen 93returns the file descriptor for the opened file, while 94.Fn fhstat , 95.Fn fhstatvfs , 96and 97.Fn fhstatvfs1 98return 0. 99Otherwise, \-1 is returned and 100.Va errno 101is set to indicate the error. 102.Sh ERRORS 103In addition to the errors returned by 104.Xr open 2 , 105.Xr fstat 2 , 106.Xr fstatvfs 2 , 107and 108.Xr fstatvfs1 2 , 109respectively, 110.Fn fhopen , 111.Fn fhstat , 112.Fn fhstatvfs , 113and 114.Fn fhstatvfs1 115will return 116.Bl -tag -width Er 117.It Bq Er EINVAL 118Calling 119.Fn fhopen 120with 121.Dv O_CREAT 122set. 123.It Bq Er ESTALE 124The file handle 125.Fa fhp 126is no longer valid. 127.El 128.Sh SEE ALSO 129.Xr fstat 2 , 130.Xr fstatvfs 2 , 131.Xr fstatvfs1 2 , 132.Xr getfh 2 , 133.Xr open 2 134.Sh HISTORY 135The 136.Fn fhopen , 137and 138.Fn fhstat 139functions first appeared in 140.Nx 1.5 . 141The 142.Fn fhstatvfs 143function replaced 144.Fn fhstatfs 145in 146.Nx 2.1 . 147