freebsd-dev/share/man/man4/snp.4

.\"
.\" $FreeBSD$
.\"
.Dd February 24, 1995
.Dt SNP 4
.Os
.Sh NAME
.Nm snp
.Nd tty snoop interface
.Sh SYNOPSIS
.In sys/snoop.h
.Ft int
.Fn ioctl fd SNPSTTY &dev
.Ft int
.Fn ioctl fd SNPGTTY &dev
.Ft int
.Fn ioctl fd FIONREAD &result
.Sh DESCRIPTION
/dev/snp? are snoop devices which allow user to attach to any tty
and watch activities on it.
The kernel must be compiled with
.Cd "device snp" ,
or the
.Nm
device must be loaded,
for these devices to be available.
.Pp
To associate a given
.Nm
device with a tty to be observed,  open the
.Nm
device and then use the SNPSTTY ioctl.
The argument passed to the IOCTL is the address of a variable of type
dev_t.
By setting the value of the variable pointed to -1, the user may detach
the snp device from a tty.
.Pp
The SNPGTTY ioctl returns information about the current tty attached to
the open
.Nm
device.
.Pp
The FIONREAD ioctl returns a positive value equal to the number of characters
in a read buffer.
Special values defined are:
.Bl -tag -width SNP_TTYCLOSE
.It Dv SNP_OFLOW
device overflow occured, device detached.
.It Dv SNP_TTYCLOSE
tty not attached.
.It Dv SNP_DETACH
.Nm
device has been detached by user or tty device has been closed
and detached.
.El
.Sh SEE ALSO
.Xr pty 4 ,
.Xr sio 4 ,
.Xr kldload 8 ,
.Xr watch 8
.Sh BUGS
Caveat emptor!
This manual page is horribly stale and wildly inaccurate in some places.
.Pp
While in line mode, user input can't be seen.
No signals may be sent to the observed tty.
.Sh AUTHORS
.An Ugen J.S. Antsilevich Aq ugen@NetVision.net.il
.Sh HISTORY
The
.Nm
device first appeared in
.Fx 2.1 .
Clean up man page 1995-02-23 01:25:48 +00:00			`.\"`
$Id$ -> $FreeBSD$ 1999-08-28 00:22:10 +00:00			`.\" $FreeBSD$`
Clean up man page 1995-02-23 01:25:48 +00:00			`.\"`
Update to reflect new calling conventions 1995-02-25 20:15:20 +00:00			`.Dd February 24, 1995`
Clean up man page 1995-02-23 01:25:48 +00:00			`.Dt SNP 4`
mdoc(7) police: removed HISTORY info from the .Os call. 2001-07-10 15:31:11 +00:00			`.Os`
Move ipfirewall.4 & snp.4 facility manpage to share/man/man4 1995-02-17 18:48:36 +00:00			`.Sh NAME`
Clean up man page 1995-02-23 01:25:48 +00:00			`.Nm snp`
			`.Nd tty snoop interface`
Move ipfirewall.4 & snp.4 facility manpage to share/man/man4 1995-02-17 18:48:36 +00:00			`.Sh SYNOPSIS`
mdoc(7) police: Use the new .In macro for #include statements. 2001-10-01 16:09:29 +00:00			`.In sys/snoop.h`
Clean up man page 1995-02-23 01:25:48 +00:00			`.Ft int`
Update to reflect new calling conventions 1995-02-25 20:15:20 +00:00			`.Fn ioctl fd SNPSTTY &dev`
Clean up man page 1995-02-23 01:25:48 +00:00			`.Ft int`
Update to reflect new calling conventions 1995-02-25 20:15:20 +00:00			`.Fn ioctl fd SNPGTTY &dev`
Clean up man page 1995-02-23 01:25:48 +00:00			`.Ft int`
Update to reflect new calling conventions 1995-02-25 20:15:20 +00:00			`.Fn ioctl fd FIONREAD &result`
Move ipfirewall.4 & snp.4 facility manpage to share/man/man4 1995-02-17 18:48:36 +00:00			`.Sh DESCRIPTION`
Clean up man page 1995-02-23 01:25:48 +00:00			`/dev/snp? are snoop devices which allow user to attach to any tty`
			`and watch activities on it.`
Talk about what the user needs to do to get the snp devices, and how watch(8) will try to help them by loading the module. PR: 25420 2001-11-24 17:02:58 +00:00			`The kernel must be compiled with`
			`.Cd "device snp" ,`
			`or the`
			`.Nm`
			`device must be loaded,`
			`for these devices to be available.`
Prepare for mdoc(7)NG. 2000-12-29 09:18:45 +00:00			`.Pp`
Clean up man page 1995-02-23 01:25:48 +00:00			`To associate a given`
mdoc(7) police: use the new features of the Nm macro. 2000-11-20 18:41:33 +00:00			`.Nm`
Clean up man page 1995-02-23 01:25:48 +00:00			`device with a tty to be observed, open the`
mdoc(7) police: use the new features of the Nm macro. 2000-11-20 18:41:33 +00:00			`.Nm`
Clean up man page 1995-02-23 01:25:48 +00:00			`device and then use the SNPSTTY ioctl.`
Update to reflect new calling conventions 1995-02-25 20:15:20 +00:00			`The argument passed to the IOCTL is the address of a variable of type`
			`dev_t.`
delete doubled words, e.g.: "the the" -> "the" 1996-10-05 18:37:31 +00:00			`By setting the value of the variable pointed to -1, the user may detach`
Update to reflect new calling conventions 1995-02-25 20:15:20 +00:00			`the snp device from a tty.`
Clean up man page 1995-02-23 01:25:48 +00:00			`.Pp`
			`The SNPGTTY ioctl returns information about the current tty attached to`
			`the open`
mdoc(7) police: use the new features of the Nm macro. 2000-11-20 18:41:33 +00:00			`.Nm`
Clean up man page 1995-02-23 01:25:48 +00:00			`device.`
			`.Pp`
			`The FIONREAD ioctl returns a positive value equal to the number of characters`
			`in a read buffer.`
			`Special values defined are:`
			`.Bl -tag -width SNP_TTYCLOSE`
			`.It Dv SNP_OFLOW`
Fix a bunch of spelling errors in a bunch of man pages. 1996-01-30 13:52:50 +00:00			`device overflow occured, device detached.`
Clean up man page 1995-02-23 01:25:48 +00:00			`.It Dv SNP_TTYCLOSE`
			`tty not attached.`
			`.It Dv SNP_DETACH`
mdoc(7) police: use the new features of the Nm macro. 2000-11-20 18:41:33 +00:00			`.Nm`
Fix a bunch of spelling errors in a bunch of man pages. 1996-01-30 13:52:50 +00:00			`device has been detached by user or tty device has been closed`
			`and detached.`
Prepare for mdoc(7)NG. 2000-12-29 09:18:45 +00:00			`.El`
Move ipfirewall.4 & snp.4 facility manpage to share/man/man4 1995-02-17 18:48:36 +00:00			`.Sh SEE ALSO`
Clean up man page 1995-02-23 01:25:48 +00:00			`.Xr pty 4 ,`
Sort cross references. 1996-12-26 16:16:37 +00:00			`.Xr sio 4 ,`
Talk about what the user needs to do to get the snp devices, and how watch(8) will try to help them by loading the module. PR: 25420 2001-11-24 17:02:58 +00:00			`.Xr kldload 8 ,`
Sort cross references. 1996-12-26 16:16:37 +00:00			`.Xr watch 8`
Move ipfirewall.4 & snp.4 facility manpage to share/man/man4 1995-02-17 18:48:36 +00:00			`.Sh BUGS`
Remove the stuff about only the superuser being able to use this (see snp.c 1.64), and add a note to the BUGS section warning the reader that this manual page is stale and may be inaccurate. 2001-11-24 17:06:20 +00:00			`Caveat emptor!`
			`This manual page is horribly stale and wildly inaccurate in some places.`
			`.Pp`
Clean up man page 1995-02-23 01:25:48 +00:00			`While in line mode, user input can't be seen.`
Fix a minor grammar bug. 1995-02-28 00:24:47 +00:00			`No signals may be sent to the observed tty.`
.Sh AUTHOR -> .Sh AUTHORS according to mdoc specs. Use .An/.Aq. 1998-03-12 07:31:21 +00:00			`.Sh AUTHORS`
			`.An Ugen J.S. Antsilevich Aq ugen@NetVision.net.il`
Move ipfirewall.4 & snp.4 facility manpage to share/man/man4 1995-02-17 18:48:36 +00:00			`.Sh HISTORY`
Clean up man page 1995-02-23 01:25:48 +00:00			`The`
mdoc(7) police: use the new features of the Nm macro. 2000-11-20 18:41:33 +00:00			`.Nm`
Use the .Fx macro for FreeBSD references for releases prior to 2.0. Use the .Tn macro for generic FreeBSD references. Cleanup other formatting problems noticed while making the above changes. 1997-03-21 20:14:15 +00:00			`device first appeared in`
			`.Fx 2.1 .`