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diff --git a/share/man/man5/fdescfs.5 b/share/man/man5/fdescfs.5 deleted file mode 100644 index fa260cbc12f3..000000000000 --- a/share/man/man5/fdescfs.5 +++ /dev/null @@ -1,218 +0,0 @@ -.\" Copyright (c) 2021 The FreeBSD Foundation, Inc. -.\" -.\" Copyright (c) 1996 -.\" Mike Pritchard <mpp@FreeBSD.org>. All rights reserved. -.\" -.\" Copyright (c) 1992, 1993, 1994 -.\" The Regents of the University of California. All rights reserved. -.\" All rights reserved. -.\" -.\" This code is derived from software donated to Berkeley by -.\" Jan-Simon Pendry. -.\" -.\" Parts of this documentation was written by -.\" Konstantin Belousov <kib@FreeBSD.org> under sponsorship -.\" from the FreeBSD Foundation. -.\" -.\" Redistribution and use in source and binary forms, with or without -.\" modification, are permitted provided that the following conditions -.\" are met: -.\" 1. Redistributions of source code must retain the above copyright -.\" notice, this list of conditions and the following disclaimer. -.\" 2. Redistributions in binary form must reproduce the above copyright -.\" notice, this list of conditions and the following disclaimer in the -.\" documentation and/or other materials provided with the distribution. -.\" 3. Neither the name of the University nor the names of its contributors -.\" may be used to endorse or promote products derived from this software -.\" without specific prior written permission. -.\" -.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND -.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE -.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE -.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE -.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL -.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS -.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) -.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT -.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY -.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF -.\" SUCH DAMAGE. -.\" -.Dd Jul 11, 2023 -.Dt FDESCFS 5 -.Os -.Sh NAME -.Nm fdescfs -.Nd file-descriptor file system -.Sh SYNOPSIS -.Bd -literal -fdescfs /dev/fd fdescfs rw 0 0 -.Ed -.Sh DESCRIPTION -The file-descriptor file system, or -.Nm , -provides access to the per-process file descriptor -namespace in the global file system namespace. -The conventional mount point is -.Pa /dev/fd . -.Pp -The file system's contents -appear as a list of numbered files -which correspond to the open files of the process reading the -directory. -The files -.Pa /dev/fd/0 -through -.Pa /dev/fd/# -refer to file descriptors which can be accessed through the file -system. -.Pp -The following mount options can be used when mounting -.Nm -filesystem: -.Bl -tag -width linrdlnk -.It Cm nodup -For file descriptors referencing vnodes, instead of the -.Xr dup 2 -semantic described above, implement re-opening of the referenced vnode. -See below for more details. -.It Cm linrdlnk -Report the type of the -.Nm -vnode as -.Dv VLNK -instead of -.Fx -traditional -.Dv VCHR . -For -.Xr linux 4 -ABI compatibility mount -.Nm -volume with the -.Cm linrdlnk -option. -.It Cm rdlnk -Treat -.Nm -vnodes as symbolic links consistently, in particular, follow -the resolved name for the name lookups. -This option is strictly stronger than the -.Cm linrdlnk -option, it changes not only the type returned by -.Xr stat 2 , -but also causes the -.Nm -files to behave as symlinks. -.El -.Pp -For -.Nm -mounted without the -.Cm nodup -mount option, -if the file descriptor is open and the mode the file is being opened -with is a subset of the mode of the existing descriptor, the call: -.Bd -literal -offset indent -fd = open("/dev/fd/0", mode); -.Ed -.Pp -and the call: -.Bd -literal -offset indent -fd = fcntl(0, F_DUPFD, 0); -.Ed -.Pp -are equivalent. -Flags to the -.Xr open 2 -call other than -.Dv O_RDONLY , -.Dv O_WRONLY -and -.Dv O_RDWR -are ignored. -.Pp -For -.Nm -mounted with the -.Cm nodup -option, and file descriptor referencing a vnode, the call: -.Bd -literal -offset indent -fd = open("/dev/fd/0", mode); -.Ed -.Pp -reopens the referenced vnode with the specified -.Fa mode . -In other words, the -.Fn open -call above is equivalent to -.Bd -literal -offset indent -fd = openat(0, "", O_EMPTY_PATH, mode); -.Ed -.Pp -In particular, if the file descriptor was opened with the -.Dv O_PATH -flag, then either -.Dv O_EMPTY_PATH -or -.Fn open -over -.Nm -mount with -.Cm nodup -option allows one to convert it to a regularly opened file, -assuming that the current permissions allow the requested -.Fa mode . -.Pp -.Em "Note:" -.Pa /dev/fd/0 , -.Pa /dev/fd/1 -and -.Pa /dev/fd/2 -files are created by default when devfs alone is mounted. -.Nm -creates entries for all file descriptors opened by the process. -.Sh FILES -.Bl -tag -width /dev/stderr -compact -.It Pa /dev/fd/# -.El -.Sh EXAMPLES -To mount a -.Nm -volume located on -.Pa /dev/fd : -.Pp -.Dl "mount -t fdescfs none /dev/fd" -.Pp -For -.Xr linux 4 -ABI compatibility: -.Pp -.Dl "mount -t fdescfs -o linrdlnk none /compat/linux/dev/fd" -.Pp -For substitute of -.Dv O_EMPTY_PATH -flag use: -.Pp -.Dl "mount -t fdescfs -o nodup none /dev/fdpath" -.Sh SEE ALSO -.Xr devfs 5 , -.Xr mount 8 -.Sh HISTORY -The -.Nm -file system first appeared in -.Bx 4.4 . -The -.Nm -manual page first appeared in -.Fx 2.2 . -.Sh AUTHORS -.An -nosplit -The -.Nm -manual page was written by -.An Mike Pritchard Aq Mt mpp@FreeBSD.org , -and was based on the -manual page written by -.An Jan-Simon Pendry . |