'\"macro stdmacro
.TH TELNET-PROBE 1 "PCP" "Performance Co-Pilot"
.SH NAME
\f3telnet-probe\f1 \- lightweight telnet-like port probe
.SH SYNOPSIS
\f3$PCP_BINADM_DIR/telnet-probe\f1
[\f3\-c\f1]
[\f3\-v\f1]
\f2host\f1 \f2port\f1
.SH DESCRIPTION
.B telnet-probe
allows the
.BR pmdashping (1)
daemons to establish connections to arbitrary local and remote
service-providing daemons so that response time and service
availability information can be obtained.
.PP
The required
.I host
and
.I port
number arguments have the same meaning as their
.BR telnet (1)
equivalents.
.PP
The
.B \-c
option causes
.B telnet-probe
to perform a
.BR connect (2)
only.
This skips the
.BR read (2)
and
.BR write (2)
exercise that would otherwise be done after connecting (see below).
.PP
The
.B \-v
option causes
.B telnet-probe
to be verbose while operating.
.PP
Once the telnet connection has been established,
.B telnet-probe
reads from
.I stdin
until end-of-file, and writes all the input data to the
telnet connection.
Next,
.B telnet-probe
will read from the telnet connection until end-of-file,
discarding whatever data it receives.
Then
.B telnet-probe
exits.
.PP
To operate successfully, the input passed via
.B telnet-probe
to the remote service must be sufficient to cause the remote service to
close the connection when the last line of input has been processed,
e.g. ending with ``quit'' when probing SMTP on port 25.
.PP
By default
.B telnet-probe
will not produce any output, unless there is an error in which case
a diagnostic message can be displayed (in verbose mode only) and the
exit status will be non-zero indicating a failure.
.SH "PCP ENVIRONMENT"
Environment variables with the prefix
.B PCP_
are used to parameterize the file and directory names
used by PCP.
On each installation, the file
.I /etc/pcp.conf
contains the local values for these variables.
The
.B $PCP_CONF
variable may be used to specify an alternative
configuration file,
as described in
.BR pcp.conf (5).
.SH DIAGNOSTICS
If
.B telnet-probe
succeeds, then 0 will be returned.
If the attempt to establish a connection fails or is terminated, then
a non-zero exit status is returned.
.SH SEE ALSO
.BR PCPintro (1),
.BR pmdashping (1),
.BR pmie (1),
.BR telnet (1),
.BR connect (2),
.BR read (2)
and
.BR write (2).