NAME
pmParseMetricSpec, pmFreeMetricSpec - uniform metric specification
parser
C SYNOPSIS
#include <pcp/pmapi.h>
int pmParseMetricSpec(const char *string, int isarch, char *source,
pmMetricSpec **rsltp, char **errmsg)
void pmFreeMetricSpec(pmMetricSpec *rslt)
cc ... -lpcp
DESCRIPTION
pmParseMetricSpec accepts a string specifying the name of a PCP
performance metric, and optionally the source (either a hostname or a
PCP archive log filename) and instances for that metric. The syntax is
described in PCPIntro(1).
If neither host nor archive component of the metric specification is
provided, the isarch and source arguments are used to fill in the
returned pmMetricSpec structure.
The pmMetricSpec structure that is returned via rsltp represents the
parsed string and has the following declaration:
typedef struct {
int isarch; /* source type: 0 -> live host, 1 -> archive, 2 -> local context */
char *source; /* name of source host or archive */
char *metric; /* name of metric */
int ninst; /* number of instances, 0 -> all */
char *inst[1]; /* array of instance names */
} pmMetricSpec;
pmParseMetricSpec returns 0 if the given string was successfully
parsed. In this case all the storage allocated by pmParseMetricSpec
can be released by a single call to free(3C) using the address returned
from pmMetricSpec via rsltp. The convenience macro pmFreeMetricSpec is
a thinly disguised wrapper for free(3C).
pmParseMetricSpec returns PM_ERR_GENERIC and a dynamically allocated
error message string in errmsg, if the given string does not parse. Be
sure to free(3C) the error message string in this situation.
In the case of an error, rsltp is undefined. In the case of success,
errmsg is undefined. If rsltp->ninst is 0, then rsltp->inst[0] is
undefined.
SEE ALSO
PMAPI(3) and pmLookupName(3).