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NAME

       pmGetInDom,  pmRequestInDom,  pmReceiveIndom - get instance identifiers
       for a performance metrics instance domain

C SYNOPSIS

       #include <pcp/pmapi.h>

       int pmGetInDom(pmInDom indom, int **instlist, char ***namelist)
       int pmRequestInDom(int ctx, pmInDom indom)
       int pmReceiveInDom(int ctx, int **instlist, char ***namelist)

       cc ... -lpcp

DESCRIPTION

       In the current Performance Metrics  Application  Programming  Interface
       (PMAPI)  context,  locate the description of the instance domain indom,
       and return via instlist  the  internal  instance  identifiers  for  all
       instances,  and  via  namelist  the  full  external identifiers for all
       instances.  The number of instances found is returned as  the  function
       value (else less than zero to indicate an error).

       The  value  for the instance domain indom is typically extracted from a
       pmDesc structure, following a call to pmLookupDesc(3) for a  particular
       performance metric.

       The  resulting  lists  of instance identifiers (instlist and namelist),
       and the names that the elements of namelist point to,  will  have  been
       allocated  by  pmGetInDom  with  two calls to malloc(3C), and it is the
       responsibility of the caller to free(instlist)  and  free(namelist)  to
       release the space when it is no longer required.

       When  the  result  of  pmGetInDom  is  less than one, both instlist and
       namelist are undefined (no space  will  have  been  allocated,  and  so
       calling free(3C) is a singularly bad idea).

       pmRequestInDom  and  pmReceiveInDom are used by applications which must
       communicate with the PMCD asynchronously.  These functions take explict
       context  handle ctx which must refer to a host context (i.e. created by
       passing PM_CONTEXT_HOST to pmNewContext). pmRequestInDom sends  request
       to  enumerate  all  instances in the particular instance domain to PMCD
       and returns  without waiting for  the  response,  pmReceiveInDom  reads
       reply  from  PMCD.  It is the responsibility of the application to make
       sure  the  data  are  ready  before  calling  pmReceiveInDom  to  avoid
       blocking.

PCP ENVIRONMENT

       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(4).  Values for these variables may be
       obtained programatically using the pmGetConfig(3) function.

SEE ALSO

       PMAPI(3),    pmGetConfig(3),     pmLookupDesc(3),     pmLookupInDom(3),
       pmNameInDom(3), pcp.conf(4) and pcp.env(4).

DIAGNOSTICS

       PM_ERR_INDOM
              indom is not a valid instance domain identifier

       PM_ERR_CTXBUSY
              Context is currently in use by another asynchronous call.