1.\" 2.\" Copyright (c) 2003 Apple Computer, Inc. All rights reserved. 3.\" 4.\" @APPLE_LICENSE_HEADER_START@ 5.\" 6.\" The contents of this file constitute Original Code as defined in and 7.\" are subject to the Apple Public Source License Version 1.1 (the 8.\" "License"). You may not use this file except in compliance with the 9.\" License. Please obtain a copy of the License at 10.\" http://www.apple.com/publicsource and read it before using this file. 11.\" 12.\" This Original Code and all software distributed under the License are 13.\" distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER 14.\" EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 15.\" INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 16.\" FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the 17.\" License for the specific language governing rights and limitations 18.\" under the License. 19.\" 20.\" @APPLE_LICENSE_HEADER_END@ 21.\" 22.Dd January 14, 2003 23.Dt FSCTL 2 24.Os "Mac OS X" 25.Sh NAME 26.Nm fsctl 27.Nd control filesystems 28.Sh SYNOPSIS 29.Fd #include <sys/attr.h> 30.Fd #include <sys/ioctl.h> 31.Ft int 32.Fn fsctl "const char *path" "unsigned long request" "void *data" "unsigned long options" 33.Sh DESCRIPTION 34The 35.Fn fsctl 36function manipulates the filesystem controlling mounted volumes. 37In particular, many filesystem-specific operating 38characteristics of mounted filesystems may be controlled 39with 40.Fn fsctl 41requests. 42.Fn fsctl 43requests can also be used to extract filesystem-specific 44information for a mounted volumes. 45.Pp 46.Fa path 47is the path name of any file within the mounted filesystem. 48An fsctl 49.Fa request 50has encoded in it whether the argument is an 51.Dq in 52parameter 53or 54.Dq out 55parameter, and the size of the argument 56.Fa data 57in bytes. 58Values for 59.Fa request 60are entirely filesystem-specific except for the following, defined in 61.Ao Pa sys/fsctl.h Ac : 62.Bd -literal -offset indent 63FSGETMOUNTINFOSIZE /* Return size of mount info data */ 64.Ed 65.Pp 66Macros and defines used in specifying an fsctl 67.Fa request 68are the same as for 69.Fn ioctl 70requests and are located in the file 71.Ao Pa sys/ioccom.h Ac . 72.Fa options 73may specify special flags for the processing of the 74.Fn fsctl 75call. The options are specified by 76.Em or Ns 'ing 77the option values. The only option currently defined is 78.Bd -literal -offset indent 79#define FSOPT_NOFOLLOW 0x00000001 /* Don't follow symlinks */ 80.Ed 81.Pp 82which is interpreted by the 83.Fn fsctl 84call to prevent following of symlinks. The 85.Fa options 86argument is passed to the filesystem, which may define and handle 87additional 88.Fa options 89bit values. 90.Sh RETURN VALUES 91.Pp 92If an error has occurred, a value of -1 is returned and 93.Va errno 94is set to indicate the error. 95.Sh ERRORS 96.Fn fsctl 97will fail if: 98.Bl -tag -width Er 99.It Bq Er ENOTDIR 100A component of the path prefix is not a directory. 101.It Bq Er ENAMETOOLONG 102A component of a pathname exceeded 103.Dv {NAME_MAX} 104characters, or an entire path name exceeded 105.Dv {PATH_MAX} 106characters. 107.It Bq Er ENOENT 108The named file does not exist. 109.It Bq Er EACCES 110Search permission is denied for a component of the path prefix. 111.It Bq Er ELOOP 112Too many symbolic links were encountered in translating the pathname. 113.It Bq Er EFAULT 114.Fa path 115or 116.Em data 117points to an invalid address. 118.It Bq Er EIO 119An 120.Tn I/O 121error occurred while reading from or writing to the file system. 122.It Bq Er EINVAL 123.Fa request 124or 125.Fa data 126is not valid. 127.El 128.Sh SEE ALSO 129.Xr ioctl 2 , 130.Xr getattrlist 2 , 131.Xr setattrlist 2 132.Sh HISTORY 133The 134.Fn fsctl 135function call appeared in Mac OS X version 10.0. 136