1.\" $NetBSD: fhopen.2,v 1.7 2002/10/02 10:36:45 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 June 29, 1999 35.Dt FHOPEN 2 36.Os 37.Sh NAME 38.Nm fhopen , 39.Nm fhstat , 40.Nm fhstatfs 41.Nd access file via file handle 42.Sh LIBRARY 43.Lb libc 44.Sh SYNOPSIS 45.Fd #include \*[Lt]sys/types.h\*[Gt] 46.Fd #include \*[Lt]sys/stat.h\*[Gt] 47.Ft int 48.Fn fhopen "const fhandle_t *fhp" "int flags" 49.Ft int 50.Fn fhstat "const fhandle_t *fhp" "struct stat *sb" 51.Ft int 52.Fn fhstatfs "const fhandle_t *fhp" "struct statfs *buf" 53.Sh DESCRIPTION 54These functions provide a means to access a file given the file handle 55.Fa fhp . 56As this method bypasses directory access restrictions, these calls are 57restricted to the superuser. 58.Pp 59.Fn fhopen 60opens the file referenced by 61.Fa fhp 62for reading and/or writing as specified by the argument 63.Fa flags 64and returns the file descriptor to the calling process. 65The 66.Fa flags 67are specified by 68.Em or Ns 'ing 69together the flags used for the 70.Xr open 2 71call. 72All said flags are valid except for 73.Dv O_CREAT . 74.Pp 75.Fn fhstat 76and 77.Fn fhstatfs 78provide the functionality of the 79.Xr fstat 2 80and 81.Xr fstatfs 2 82calls except that they return information for the file referred to by 83.Fa fhp 84rather than an open file. 85.Sh RETURN VALUES 86Upon successful completion, 87.Fn fhopen 88returns the file descriptor for the opened file, while 89.Fn fhstat 90and 91.Fn fhstatfs 92return 0. 93Otherwise, -1 is returned and 94.Va errno 95is set to indicate the error. 96.Sh ERRORS 97In addition to the errors returned by 98.Xr open 2 , 99.Xr fstat 2 , 100and 101.Xr fstatfs 2 102respectively, 103.Fn fhopen , 104.Fn fhstat , 105and 106.Fn fhstatfs 107will return 108.Bl -tag -width Er 109.It Bq Er EINVAL 110Calling 111.Fn fhopen 112with 113.Dv O_CREAT 114set. 115.It Bq Er ESTALE 116The file handle 117.Fa fhp 118is no longer valid. 119.El 120.Sh SEE ALSO 121.Xr fstat 2 , 122.Xr fstatfs 2 , 123.Xr getfh 2 , 124.Xr open 2 125.Sh HISTORY 126The 127.Fn fhopen , 128.Fn fhstat , 129and 130.Fn fhstatfs 131functions first appeared in 132.Nx 1.5 . 133