1.\" $NetBSD: opendisk.3,v 1.13 2016/06/07 11:20:45 wiz Exp $ 2.\" 3.\" Copyright (c) 1997, 2001 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to The NetBSD Foundation 7.\" by Luke Mewburn. 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.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 19.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 20.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 21.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 22.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28.\" POSSIBILITY OF SUCH DAMAGE. 29.\" 30.Dd June 6, 2016 31.Dt OPENDISK 3 32.Os 33.Sh NAME 34.Nm opendisk 35.Nd open a disk partition 36.Sh LIBRARY 37.Lb libutil 38.Sh SYNOPSIS 39.In util.h 40.Ft int 41.Fo opendisk 42.Fa "const char *path" 43.Fa "int flags" 44.Fa "char *buf" 45.Fa "size_t buflen" 46.Fa "int iscooked" 47.Fc 48.Sh DESCRIPTION 49.Fn opendisk 50opens 51.Fa path , 52for reading and/or writing as specified by the argument 53.Fa flags 54using 55.Xr open 2 , 56and the file descriptor is returned to the caller. 57.Fa buf 58is used to store the resultant filename. 59.Fa buflen 60is the size, in bytes, of the array referenced by 61.Fa buf 62(usually 63.Dv MAXPATHLEN 64bytes). 65.Fa iscooked 66controls which paths in 67.Pa /dev 68are tried. 69.Pp 70.Fn opendisk 71attempts to open the following variations of 72.Fa path , 73in order: 74.Pp 75If 76.Fa path 77does not contain a 78slash 79.Pq Dq / , 80the following variations are attempted: 81.Pp 82.Bl -dash -compact 83.It 84If 85.Fa iscooked 86is zero: 87.Bl -tag -compact -width "/dev/rpathX" 88.It Pa /dev/rpath 89.Fa path 90with a prefix of 91.Dq Pa /dev/r . 92.It Pa /dev/rpath Ns Em X 93.Fa path 94with a prefix of 95.Dq Pa /dev/r 96and a suffix of 97.Sq Em X 98(q.v.). 99.El 100.It 101If 102.Fa iscooked 103is non-zero: 104.Bl -tag -compact -width "/dev/rpathX" 105.It Pa /dev/path 106.Fa path 107with a prefix of 108.Dq Pa /dev/ . 109.It Pa /dev/path Ns Em X 110.Fa path 111with a prefix of 112.Dq Pa /dev/ 113and a suffix of 114.Sq Em X 115(q.v.). 116.El 117.El 118.Pp 119If the above fails, then the original 120.Fa path 121is tried using the following two variations: 122.Pp 123.Bl -dash -compact 124.It 125The 126.Fa iscooked 127value is ignored: 128.Bl -tag -compact -width "/dev/rpathX" 129.It Pa path 130The pathname as given. 131.It Pa path Ns Em X 132.Fa path 133with a suffix of 134.Sq Em X , 135where 136.Sq Em X 137represents the raw partition of the device, as determined by 138.Xr getrawpartition 3 , 139usually 140.Dq c . 141.El 142.El 143.Sh RETURN VALUES 144An open file descriptor, or -1 if the 145.Xr open 2 146failed. 147.Sh ERRORS 148.Fn opendisk 149may set 150.Va errno 151to one of the following values: 152.Bl -tag -width Er 153.It Bq Er EFAULT 154.Fa buf 155was the 156.Dv NULL 157pointer. 158.It Bq Er EINVAL 159.Dv O_CREAT 160was set in 161.Fa flags , 162or 163.Xr getrawpartition 3 164didn't return a valid partition. 165.El 166.Pp 167The 168.Fn opendisk 169function 170may also set 171.Va errno 172to any value specified by the 173.Xr open 2 174function. 175.Sh SEE ALSO 176.Xr open 2 , 177.Xr getrawpartition 3 178.Sh HISTORY 179The 180.Fn opendisk 181function first appeared in 182.Nx 1.3 . 183.Pp 184The lookup order of 185.Fn opendisk 186was changed in 187.Nx 8 188to first look in 189.Pa /dev 190in order to avoid opening random files in the current working directory. 191