lucyc@jpl-devvax.jpl.nasa.gov (Lucy Chao) (09/06/89)
Dear UNIX Experts : We had just recently converted to SunOS4.0 from SunOS3.5. And to our surprise, the system adjtime() routine had been changed in SunOS4.0. In version 3.5, the adjtime() routine would always speed up or slow down the system's clock by 10% (a fixed percentage) -- which means that for every 10 seconds, the system's clock would slow down or speed up 1 second. So in version 3.5, if somebody calls adjtime(), he (or she) will be able to calculate how long it will take for the system's clock to be fully adjusted. However, in version 4.0, the adjtime() has been changed; the time adjustment is now effected by speeding up or slowing down the system's clock by some small percentage, generally a fraction of one percent. And when we actually tried adjusting time with the the adjtime() routine in version 4.0, the system's clock was adjusted at such a rapid speed (in comparison with the adjtime() in SunOS3.5) that it is difficult to estimate the exact percentage based on which the system's clock is adjusted. According the the system man page, the rate of the time adjustment in OS4.0 MAY very will be variable based on some "unknown" factors; it may even be an unknown function based on the amount of time that needs to be corrected. And to our knowledge, at this point, the system built in man page is our only source of information on the adjtime() routine. IS THERE ANYBODY OUT THERE WHO KNOWS WHAT THIS "UNKNOWN" FUNCTION OR FRACTION OF PERCENTAGE MAY BE IN SUNOS 4.0 ??? DOES ANYBODY KNOWS ANYTHING THAT MAY HELP US TO ESTIMATE THE AMOUNT OF TIME NEEDED BY THE 4.0 adjtime() TO COMPLETE THE TIME ADJUSTMENT REQUESTED ?? I would really appreciate any help from anybody on this. Thank You So Very Much !! Sincerely, Lucy Chao