hartmannathan commented on pull request #1005: URL: https://github.com/apache/incubator-nuttx-apps/pull/1005#issuecomment-1040526737
> @xiaoxiang781216 what happened to CLOCK_REALTIME? If I'm not wrong CLOCK_REALTIME is affected when you change the time/date and CLOCK_MONOTONIC is not. Isn't going break some application and/or Linux/POSIX compatibility? For measuring elapsed time in fact CLOCK_MONOTONIC is the solution, but I guess there are cases where CLOCK_REALTIME could be useful. More info: https://stackoverflow.com/questions/3523442/difference-between-clock-realtime-and-clock-monotonic http://www.qnx.com/developers/docs/qnxcar2/index.jsp?topic=%2Fcom.qnx.doc.neutrino.getting_started%2Ftopic%2Fs1_timer_CLOCK_MONOTONIC.html https://tagmerge.com/question/difference-between-clock_realtime-and-clock_monotonic?answer=61e1f9684f0d313df01d4719 CLOCK_REALTIME can go "backwards" due to clock changes, daylight saving time, leap seconds, NTP, and other reasons. For measuring elapsed time you definitely want CLOCK_MONOTONIC. From memory, I think both clocks are present in POSIX at minimum; then there are other clocks like, e.g., CLOCK_BOOTTIME that are not guaranteed to be present. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: commits-unsubscr...@nuttx.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
