TELNET-PROBE(1)            General Commands Manual           TELNET-PROBE(1)

NAME         top

       telnet-probe - lightweight telnet-like port probe

SYNOPSIS         top

       $PCP_BINADM_DIR/telnet-probe [-c] [-v] host port

DESCRIPTION         top

       telnet-probe allows the pmdashping(1) daemons to establish
       connections to arbitrary local and remote service-providing daemons
       so that response time and service availability information can be

       The required host and port number arguments have the same meaning as
       their telnet(1) equivalents.

       The -c option causes telnet-probe to perform a connect(2) only.  This
       skips the read(2) and write(2) exercise that would otherwise be done
       after connecting (see below).

       The -v option causes telnet-probe to be verbose while operating.

       Once the telnet connection has been established, telnet-probe reads
       from stdin until end-of-file, and writes all the input data to the
       telnet connection.  Next, telnet-probe will read from the telnet
       connection until end-of-file, discarding whatever data it receives.
       Then telnet-probe exits.

       To operate successfully, the input passed via 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.

       By default 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


       Environment variables with the prefix PCP_ are used to parameterize
       the file and directory names used by PCP.  On each installation, the
       file /etc/pcp.conf contains the local values for these variables.
       The $PCP_CONF variable may be used to specify an alternative
       configuration file, as described in pcp.conf(5).

DIAGNOSTICS         top

       If 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.

SEE ALSO         top

       PCPintro(1), pmdashping(1), pmie(1), telnet(1), connect(2), read(2)
       and write(2).

COLOPHON         top

       This page is part of the PCP (Performance Co-Pilot) project.
       Information about the project can be found at ⟨⟩.
       If you have a bug report for this manual page, send it to  This page was obtained from the project's upstream
       Git repository ⟨⟩ on
       2019-05-09.  (At that time, the date of the most recent commit that
       was found in the repository was 2019-05-08.)  If you discover any
       rendering problems in this HTML version of the page, or you believe
       there is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to

Performance Co-Pilot                 PCP                     TELNET-PROBE(1)