NAME

       pmaRewriteMeta - try to change the version of an archive metadata record

C SYNOPSIS

       #include <pcp/pmapi.h>
       #include <pcp/libpcp.h>
       #include <pcp/archive.h>

       int pmaRewriteMeta(__pmLogCtl *inlcp, __pmLogCtl *outlcp, __int32_t *rbuf);

       cc ... -lpcp_archive -lpcp

CAVEAT

       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.

DESCRIPTION

       A physical metadata record from the input archive identified by inlcp is passed in via rbuf and  this  is
       reformatted  if  required  to produce the equivalent metadata record for the output archive identified by
       outlcp.

       Combined with the input and output archive versions, the type of the metadata record (as  extracted  from
       rbuf) is used to decide if; for some record types and version changes no rewriting is required.

       pmaRewriteMeta  is  intended  to  be  used  in  cases  where  the archive version of inlcp and outlcp are
       differerent.  The only sane choice of archive versions today is PM_LOG_VERS02 for inlcp and PM_LOG_VERS03
       for outlcp, which would be requesting a rewrite from archive version 2 format to archive version 3 format
       (as only versions 2 and 3 are currently supported).

       If rewriting takes place the old rbuf will have been free'd and a new rbuf allocated with malloc(3).   It
       is  the  caller's  responsibility  to  make  sure  this potential free-and-allocate will be safe, e.g. no
       dangling references into the contents of rbuf, or pass in a copy of the record if it is precious.

DIAGNOSTICS AND RETURN VALUES

       In several places, fatal errors will trigger an error message and force the application to exit.

       If there is no defined translation for the versions of  inlcp  and  outlcp  then  pmaRewriteMeta  returns
       PM_ERR_APPVERSION (a slight perversion of this error code).

       If  no rewrite is performed, the return value is 0, otherwise a return value of 1 indicates a rewrite has
       taken place and rbuf has been reallocated.

SEE ALSO

       free(3), malloc(3), PMAPI(3), and pmaRewriteData(3).

Performance Co-Pilot                                   PCP                                     PMAREWRITEMETA(3)