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28 .Dd September 25, 2017
34 .Nd "event rate limiting"
38 .Fn ratecheck "struct timeval *lasttime" "struct timeval *mininterval"
40 .Fn ppsratecheck "struct timeval *lasttime" "int *curpps" "int maxpps"
46 functions facilitate rate-limiting of arbitrary events.
47 The former enforces a minimum interval between events while the latter
48 enforces a maximum number of events per second.
52 function compares the current time to the value pointed to by
54 If the difference is equal to or greater than
56 it returns a non-zero value and updates
59 Otherwise, it returns zero.
63 function first compares the current time
66 If at least a full second has passed, the value pointed to by the
68 argument is reset to 1 and
70 is updated to the current time.
78 returns a non-zero value if and only if the updated
80 is less than or equal to
92 functions first appeared in