man7.org > Linux > man-pages

Linux/UNIX system programming training

pmgetversion(3) — Linux manual page

NAME | C SYNOPSIS | DESCRIPTION | EXAMPLE | SEE ALSO | COLOPHON 

PMGETVERSION(3)         Library Functions Manual         PMGETVERSION(3)

NAME         top

       pmGetVersion - fetch installed PCP version number

C SYNOPSIS         top

       #include <pcp/pmapi.h>

       int pmGetVersion(void);

       cc ... -lpcp

DESCRIPTION         top

       pmGetVersion returns a binary encoding of the locally installed
       PCP version number.

       This may be used in conjunction with the related macros
       PM_VERSION(a,b,c) and PM_VERSION_CURRENT that generate PCP
       version numbers in the same format.  Refer to the example below.

       The encoding uses one byte for each of the parts of the version
       number of the installed PCP package, namely the major number, the
       minor number and the revision number.  So PCP version 3.10.5 is
       encoded as 0x30a05.

       The string format of the installed PCP package version number as
       also available from pmGetConfig with the argument PCP_VERSION.

       pmGetVersion was introduced in PCP 3.10.5.

EXAMPLE         top

       The following C fragment demonstrates the use of both the
       compile-time macros and the run-time pmGetVersion function for an
       application that should not be built for PCP versions older than
       3.10.5, but after that there are two alternative implementations
       with a newer (faster, sweeter, smaller) variant of the XYZ
       service that only becoming available in PCP 4.0.0.

       #include <pcp/pmapi.h>

       #ifdef PM_VERSION_CURRENT
       #if PM_VERSION_CURRENT < PM_VERSION(3,10,5)
           /* no pmGetVersion() before PCP 3.10.5 */
           printf("PCP version 0x%x too old\n", PM_VERSION_CURRENT);
       #endif
           version = pmGetVersion();
           if (version >= PM_VERSION(4,0,0) {
            /* V2 of the XYZ service introduced in PCP 4.0.0 */
            printf("Using V2 of service XYZ\n")
            ...
           }
           else {
            printf("Using V1 of service XYZ\n")
            ...
           }
       #else
           {
            char *ver = pmGetConfig("PCP_VERSION");
            /* only option is to extract version number from returned string */
            ...
           }
       #endif

SEE ALSO         top

       PMAPI(3), and pmGetConfig(3).

COLOPHON         top

       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 pcp@groups.io.  This page was obtained from the
       project's upstream Git repository
       ⟨https://github.com/performancecopilot/pcp.git⟩ on 2024-06-14.
       (At that time, the date of the most recent commit that was found
       in the repository was 2024-06-14.)  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
       man-pages@man7.org

Performance Co-Pilot               PCP                   PMGETVERSION(3)

Pages that refer to this page: pmgetconfig(3)

HTML rendering created 2024-06-26 by Michael Kerrisk, author of The Linux Programming Interface.

For details of in-depth Linux/UNIX system programming training courses that I teach, look here.

Hosting by jambit GmbH.

Cover of TLPI