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diff --git a/sbin/mount_std/mount_procfs.8 b/sbin/mount_std/mount_procfs.8 new file mode 100644 index 0000000..3aa20e0 --- /dev/null +++ b/sbin/mount_std/mount_procfs.8 @@ -0,0 +1,253 @@ +.\" +.\" Copyright (c) 1992, 1993 +.\" 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. +.\" +.\" 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. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed by the University of +.\" California, Berkeley and its contributors. +.\" 4. 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. +.\" +.\" @(#)mount_procfs.8 8.2 (Berkeley) 3/27/94 +.\" +.\" +.Dd March 27, 1994 +.Dt MOUNT_PROCFS 8 +.Os BSD 4.4 +.Sh NAME +.Nm mount_procfs +.Nd mount the process file system +.Sh SYNOPSIS +.Nm mount_procfs +.Op Fl o Ar options +.Pa /proc +.Pa mount_point +.Sh DESCRIPTION +The +.Nm mount_procfs +command attaches an instance of the process +namespace to the global filesystem namespace. +The conventional mount point is +.Pa /proc . +This command is normally executed by +.Xr mount 8 +at boot time. +.Pp +The options are as follows: +.Bl -tag -width indent +.It Fl o +Options are specified with a +.Fl o +flag followed by a comma separated string of options. +See the +.Xr mount 8 +man page for possible options and their meanings. +.El +.Pp +The root of the process filesystem +contains an entry for each active process. +These processes are visible as a directory whose +name is the process' pid. +In addition, the special entry +.Pa curproc +references the current process. +.Pp +Each directory contains several files. +.Bl -tag -width status +.It Pa ctl +a writeonly file which supports a variety +of control operations. +Control commands are written as strings to the +.Pa ctl +file. +The control commands are: +.Bl -tag -width detach -compact +.It attach +stops the target process and arranges for the sending +process to become the debug control process. +.It detach +continue execution of the target process and +remove it from control by the debug process (which +need not be the sending process). +.It run +continue running the target process until +a signal is delivered, a breakpoint is hit, or the +target process exits. +.It step +single step the target process, with no signal delivery. +.It wait +wait for the target process to come to a steady +state ready for debugging. +The target process must be in this state before +any of the other commands are allowed. +.El +.Pp +The string can also be the name of a signal, lower case +and without the +.Dv SIG +prefix, +in which case that signal is delivered to the process +(see +.Xr sigaction 2 ). +.It Pa file +A reference to the vnode from which the process text was read. +This can be used to gain access to the process' symbol table, +or to start another copy of the process. +.It Pa mem +The complete virtual memory image of the process. +Only those address which exist in the process can be accessed. +Reads and writes to this file modify the process. +Writes to the text segment remain private to the process. +.It Pa note +Not implemented. +.It Pa notepg +Not implemented. +.It Pa regs +Allows read and write access to the process' register set. +This file contains a binary data structure +.Dv "struct regs" +defined in +.Pa <machine/reg.h> . +.Pa regs +can only be written when the process is stopped. +.It Pa fpregs +The floating point registers as defined by +.Dv "struct fpregs" +in +.Pa <machine/reg.h> . +.Pa fpregs +is only implemented on machines which have distinct general +purpose and floating point register sets. +.It Pa status +The process status. +This file is readonly and returns a single line containing +multiple space-separated fields as follows: +.Pp +.Bl -bullet -compact +.It +command name +.It +process id +.It +parent process id +.It +process group id +.It +session id +.It +.Ar major,minor +of the controlling terminal, or +.Dv -1,-1 +if there is no controlling terminal. +.It +a list of process flags: +.Dv ctty +if there is a controlling terminal, +.Dv sldr +if the process is a session leader, +.Dv noflags +if neither of the other two flags are set. +.It +the process start time in seconds and microseconds, +comma separated. +.It +the user time in seconds and microseconds, +comma separated. +.It +the system time in seconds and microseconds, +comma separated. +.It +the wait channel message +.It +the process credentials consisting of +the effective user id +and the list of groups (whose first member +is the effective group id) +all comma separated. +.El +.El +.Pp +In a normal debugging environment, +where the target is fork/exec'd by the debugger, +the debugger should fork and the child should stop +itself (with a self-inflicted +.Dv SIGSTOP +for example). +The parent should issue a +.Dv wait +and then an +.Dv attach +command via the appropriate +.Pa ctl +file. +The child process will receive a +.Dv SIGTRAP +immediately after the call to exec (see +.Xr execve 2 ). +.Sh FILES +.Bl -tag -width /proc/curproc -compact +.It Pa /proc/# +.It Pa /proc/curproc +.It Pa /proc/curproc/ctl +.It Pa /proc/curproc/file +.It Pa /proc/curproc/mem +.It Pa /proc/curproc/note +.It Pa /proc/curproc/notepg +.It Pa /proc/curproc/regs +.It Pa /proc/curproc/fpregs +.It Pa /proc/curproc/status +.El +.Sh SEE ALSO +.Xr sigaction 2 , +.Xr mount 2 , +.Xr unmount 2 , +.Sh CAVEATS +No +.Pa . +and +.Pa .. +entries appear when listing the contents of the +.Pa /proc +directory. +This makes sense in the context of this filesystem, but is inconsistent +with usual filesystem conventions. +However, it is still possible to refer to both +.Pa . +and +.Pa .. +in a pathname. +.Pp +This filesystem may not be NFS-exported +since most of the functionality of +.Dv procfs +requires that state be maintained. +.Sh HISTORY +The +.Nm mount_procfs +utility first appeared in 4.4BSD. |