r3 - 2011-03-17 - 19:53:42 - HarlanStennYou are here: NTP >  Dev Web > DevelopmentIssues > RefclockShmV2
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SHM Refclock Driver, V2

Related Topics: bug_small.png Bug #1232


refclock_shm.c says, in part:

To add new modes: Extend or union the shmTime-struct. Do not extend/shrink size, because otherwise existing implementations will specify wrong size of shared memory-segment

PB 18.3.97

struct shmTime {
        int    mode; /* 0 - if valid set
                      *       use values,
                      *       clear valid
                      * 1 - if valid set
                      *       if count before and after read of values is equal,
                      *         use values
                      *       clear valid
        int    count;
        time_t clockTimeStampSec;
        int    clockTimeStampUSec;
        time_t receiveTimeStampSec;
        int    receiveTimeStampUSec;
        int    leap;
        int    precision;
        int    nsamples;
        int    valid;
        int    dummy[10];


  • Add a version number to struct shmTime
  • Support nanoseconds
  • We have a precision field. Do we also need a way to specify the particular CTL_SST_TS* value?

Proposed Changes


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