This documentation is intended for internal Performance Co-Pilot
(PCP) developer use.
These interfaces are not part of the PCP APIs that are guaranteed to
remain fixed across releases, and they may not work, or may provide
different semantics at some point in the future.
Each instance of the Performance Co-Pilot (PCP) archive logger
program pmlogger(1) supports a control port on which
__pmControlLog(3) requests are received, and responses sent.
Optionally, the pmlogger(1) instance may be designated the
__pmConnectLogger may be used to establish a control port connection
to the pmlogger(1) instance identified by process id pid on the host
One special case is supported; for the reserved pid value of
PM_LOG_CONTROL_PORT the requested connection is to the control port
for the ``primary'' logger, whatever its process id might be.
On success, __pmConnectLogger returns a non-negative integer, that is
a file descriptor that may be used in subsequent communication with
the pmlogger(1) instance, e.g. for __pmControlLog(3).
As the control port to pmlogger(1) is not mulitplexed, applications
using __pmConnectLogger should use close(2) to terminate the
connection to pmlogger(1) as soon as they have finished
If the application connects, and the pmlogger(1) instance
subsequently terminates, e.g. because the associated pmcd(1) instance
is terminated, the application will have to explicitly re-establish
connection to a re-started pmlogger(1) instance by calling
no permission to connect to the specified pmlogger(1) instance
the designated pmlogger(1) instance does not exist
the requested control port is already in use
This page is part of the PCP (Performance Co-Pilot) project.
Information about the project can be found at ⟨http://www.pcp.io/⟩.
If you have a bug report for this manual page, send it to
firstname.lastname@example.org. This page was obtained from the project's upstream
Git repository ⟨https://github.com/performancecopilot/pcp.git⟩ on
2020-06-09. (At that time, the date of the most recent commit that
was found in the repository was 2020-06-09.) 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 PMCONNECTLOGGER(3)