1.\" Copyright (c) 1998 Robert Nordier 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in 11.\" the documentation and/or other materials provided with the 12.\" distribution. 13.\" 14.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS 15.\" OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 16.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY 18.\" DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE 20.\" GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 21.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER 22.\" IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 23.\" OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN 24.\" IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25.\" 26.\" $FreeBSD$ 27.\" 28.Dd December 8, 2007 29.Dt NEWFS_MSDOS 8 30.Os 31.Sh NAME 32.Nm newfs_msdos 33.Nd construct a new MS-DOS (FAT) file system 34.Sh SYNOPSIS 35.Nm 36.Op Fl N 37.Op Fl B Ar boot 38.Op Fl F Ar FAT-type 39.Op Fl I Ar volid 40.Op Fl L Ar label 41.Op Fl O Ar OEM 42.Op Fl S Ar sector-size 43.Op Fl a Ar FAT-size 44.Op Fl b Ar block-size 45.Op Fl c Ar cluster-size 46.Op Fl e Ar dirents 47.Op Fl f Ar format 48.Op Fl h Ar heads 49.Op Fl i Ar info 50.Op Fl k Ar backup 51.Op Fl m Ar media 52.Op Fl n Ar FATs 53.Op Fl o Ar hidden 54.Op Fl r Ar reserved 55.Op Fl s Ar total 56.Op Fl u Ar track-size 57.Ar special 58.Op Ar disktype 59.Sh DESCRIPTION 60The 61.Nm 62utility creates a FAT12, FAT16, or FAT32 file system on device 63.Ar special , 64using 65.Xr disktab 5 66entry 67.Ar disktype 68to determine geometry, if required. 69.Pp 70The options are as follow: 71.Bl -tag -width indent 72.It Fl N 73Do not create a file system: just print out parameters. 74.It Fl B Ar boot 75Get bootstrap from file. 76.It Fl F Ar FAT-type 77FAT type (one of 12, 16, or 32). 78.It Fl I Ar volid 79Volume ID. 80.It Fl L Ar label 81Volume label (up to 11 characters). 82The label should consist of 83only those characters permitted in regular DOS (8+3) filenames. 84.It Fl O Ar OEM 85OEM string (up to 8 characters). 86The default is 87.Qq Li "BSD 4.4" . 88.It Fl S Ar sector-size 89Number of bytes per sector. 90Acceptable values are powers of 2 91in the range 128 through 32768. 92.It Fl a Ar FAT-size 93Number of sectors per FAT. 94.It Fl b Ar block-size 95File system block size (bytes per cluster). 96This should resolve to an 97acceptable number of sectors per cluster (see below). 98.It Fl c Ar cluster-size 99Sectors per cluster. 100Acceptable values are powers of 2 in the range 1011 through 128. 102.It Fl e Ar dirents 103Number of root directory entries (FAT12 and FAT16 only). 104.It Fl f Ar format 105Specify a standard (floppy disk) format. 106The standard formats 107are (capacities in kilobytes): 160, 180, 320, 360, 640, 720, 1200, 1081232, 1440, 2880. 109.It Fl h Ar heads 110Number of drive heads. 111.It Fl i Ar info 112Location of the file system info sector (FAT32 only). 113A value of 0xffff signifies no info sector. 114.It Fl k Ar backup 115Location of the backup boot sector (FAT32 only). 116A value 117of 0xffff signifies no backup sector. 118.It Fl m Ar media 119Media descriptor (acceptable range 0xf0 to 0xff). 120.It Fl n Ar FATs 121Number of FATs. 122Acceptable values are 1 to 16 inclusive. 123The default 124is 2. 125.It Fl o Ar hidden 126Number of hidden sectors. 127.It Fl r Ar reserved 128Number of reserved sectors. 129.It Fl s Ar total 130File system size. 131.It Fl u Ar track-size 132Number of sectors per track. 133.El 134.Sh NOTES 135FAT file system parameters occupy a "Boot Sector BPB (BIOS Parameter 136Block)" in the first of the "reserved" sectors which precede the actual 137file system. 138For reference purposes, this structure is presented 139below. 140.Bd -literal 141struct bsbpb { 142 u_int16_t bps; /* [-S] bytes per sector */ 143 u_int8_t spc; /* [-c] sectors per cluster */ 144 u_int16_t res; /* [-r] reserved sectors */ 145 u_int8_t nft; /* [-n] number of FATs */ 146 u_int16_t rde; /* [-e] root directory entries */ 147 u_int16_t sec; /* [-s] total sectors */ 148 u_int8_t mid; /* [-m] media descriptor */ 149 u_int16_t spf; /* [-a] sectors per FAT */ 150 u_int16_t spt; /* [-u] sectors per track */ 151 u_int16_t hds; /* [-h] drive heads */ 152 u_int32_t hid; /* [-o] hidden sectors */ 153 u_int32_t bsec; /* [-s] big total sectors */ 154}; 155/* FAT32 extensions */ 156struct bsxbpb { 157 u_int32_t bspf; /* [-a] big sectors per FAT */ 158 u_int16_t xflg; /* control flags */ 159 u_int16_t vers; /* file system version */ 160 u_int32_t rdcl; /* root directory start cluster */ 161 u_int16_t infs; /* [-i] file system info sector */ 162 u_int16_t bkbs; /* [-k] backup boot sector */ 163}; 164.Ed 165.Sh LIMITATION 166The maximum file size is 4GB, even if the file system itself is bigger. 167.Sh EXIT STATUS 168Exit status is 0 on success and 1 on error. 169.Sh EXAMPLES 170.Bd -literal -offset indent 171newfs_msdos /dev/ad0s1 172.Ed 173.Pp 174Create a file system, using default parameters, on 175.Pa /dev/ad0s1 . 176.Bd -literal -offset indent 177newfs_msdos -f 1440 -L foo fd0 178.Ed 179.Pp 180Create a standard 1.44M file system, with volume label 181.Ar foo , 182on 183.Pa /dev/fd0 . 184.Sh SEE ALSO 185.Xr disktab 5 , 186.Xr disklabel 8 , 187.Xr fdisk 8 , 188.Xr newfs 8 189.Sh HISTORY 190The 191.Nm 192utility first appeared in 193.Fx 3.0 . 194.Sh AUTHORS 195.An Robert Nordier Aq rnordier@FreeBSD.org . 196