1PMPARSETIMEWINDOW(3) Library Functions Manual PMPARSETIMEWINDOW(3)
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6 pmParseTimeWindow - parse time window command line arguments
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9 #include <pcp/pmapi.h>
10 int pmParseTimeWindow(const char *swStart, const char *swEnd,
12 const char *swAlign, const char *swOffset,
13 const struct timeval *logStart, const struct timeval *logEnd,
14 struct timeval *rsltStart, struct timeval *rsltEnd,
15 struct timeval *rsltOffset, char **errMsg);
16 cc ... -lpcp
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20 pmParseTimeWindow is designed to encapsulate the interpretation of the
21 -S, -T, -A and -O command line options used by Performance Co-Pilot
22 (PCP) applications to define a time window of interest. The time win‐
23 dow is defined by a start time and an end time that constrains the time
24 interval during which the PCP application will retrieve and display
25 performance metrics. In the absence of the -O and -A options to speci‐
26 fy an initial sample time origin and time alignment (see below), the
27 PCP application will retrieve the first sample at the start of the time
28 window.
29 The syntax and meaning of the various argument formats for these op‐
31 tions is described in PCPIntro(1).
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34 pmParseTimeWindow expects to be called with the argument of the -S op‐
35 tion as swStart, the argument of the -T option as swEnd, the argument
36 of the -A option as swAlign, and the argument of the -O option as
37 swOffset. Any or all of these parameters may be NULL to indicate that
38 the corresponding command line option was not present.
39 If the application is using a set of PCP archive logs as the source of
41 performance metrics, you also need to supply the time of the first ar‐
42 chive log entry as logStart, and the time of the last archive log entry
43 as logEnd. See pmGetArchiveLabel(3) and pmGetArchiveEnd(3) for how to
44 obtain values for these times.
45 If the application is manipulating multiple concurrent archive logs,
47 then the caller must resolve how the default time window is to be de‐
48 fined (the union of the time intervals in all archive logs is a likely
49 interpretation).
50 If the application is using a live feed of performance data, logStart
52 should be the current time (but could be aligned on the next second for
53 example), while logEnd should have its tv_sec component set to INT_MAX.
54 The rsltStart, rsltEnd and rsltOffset structures must be allocated be‐
56 fore calling pmParseTimeWindow.
57 You also need to set the current PCP reporting time zone to correctly
59 reflect the -z and -Z command line parameters before calling pmParse‐
60 TimeWindow. See pmUseZone(3) and friends for information on how this
61 is done.
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64 If the conversion is successful, pmParseTimeWindow returns 1 and fills
65 in rsltStart, rsltEnd and rsltOffset with the start, end, and offset
66 times for the time window defined by the input parameters. The errMsg
67 parameter is not changed when pmParseTimeWindow returns 1.
68 If the conversion is successful, but the requested alignment could not
70 be performed (e.g. the set of PCP archive logs is too short) the align‐
71 ment is ignored, rsltStart, rsltEnd and rsltOffset are filled in and
72 pmParseTimeWindow returns 0. In this case, errMsg will point to a
73 warning message in a dynamically allocated buffer. The caller is re‐
74 sponsible for releasing the buffer by calling free(3).
75 If the argument strings could not be parsed, pmParseTimeWindow returns
77 -1. In this case, errMsg will point to an error message in a dynami‐
78 cally allocated buffer. The caller is responsible for releasing the
79 buffer by calling free(3).
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82 free(3), PMAPI(3), pmGetArchiveEnd(3), pmGetArchiveLabel(3), pmNewCon‐
83 textZone(3), pmNewZone(3), pmParseInterval(3) and pmUseZone(3).
84Performance Co-Pilot PCP PMPARSETIMEWINDOW(3)