7 ms·

> It even handles that crazy case where you want to run on a specific day of the week. Does it handle the, in my opinion, not crazy case of running something e

> It even handles that crazy case where you want to run on a specific day of the week. Does it handle the, in my opinion, not crazy case of running something every, say, 100 seconds?

borski 10y ago
Sadly, no. The minimum granularity is in minutes.
- Bromskloss 10y ago
  What about every 100 minutes?
  - bahjoite 10y ago
    */100 * * * * echo "every 100 mins"
    - soneil 10y ago
      Have you tried this? Since minute only counts from 0-59, it's never divisible by 100. I have a similar problem with "every 2 days". */2 looks simple enough, but it fires on the 29th, miss 30th, fires on 31st, then fires the 1st. 3 times in 4 days isn't "every 2 days". Cron only works for periods which are evenly divisible into the calendar. "every 7 minutes" doesn't work because 60 isn't evenly divisible by 7. "every 5 hours" doesn't work (in that it'll match 8pm and midnight, which are only 4 hours apart), etc.
      - gkya 10y ago
        Well in cron "every two days" is more like "every second day of a month", and "ever 5 hours" like "every fifth hour of a day".
        soneil 10y ago
        I guess that's what I was getting at. "every 100 minutes" doesn't work, because cron reads it as "every 100th minute of an hour".
      - bahjoite 10y ago
        You're right; thank you for pointing out my mistake. Every day's a school day.
      - jwilk 10y ago
        0 is divisible is by 100.
  - jstimpfle 10y ago
    It's not designed for frequencies that don't align well with the partition of time in months, weeks, days, hours, minutes. But you probably can tweak your requirement slightly.
  - edoceo 10y ago
    With fcron the line looks like @100 /do/my/thing.sh
    - pekeler 10y ago
      Is fcron stateful so that it remembers if the schedule started today at midnight, the first time it should run tomorrow is at 1am?
      - edoceo 10y ago
        As far as I can tell and if IIRC its across reboots too. I can't remember all the reasons I moved to fcron (10+ years ago) but the @# syntax was one factor
        Bromskloss 10y ago
        > the @# syntax Watch your language!
  - mappu 10y ago
    If you're really stuck with this requirement, and vixie cron is your only tool: */1 * * * * /usr/bin/bash -c '[[ $(( $(/usr/bin/date +%s) % 6000)) -eq 0 ]] && mycommand'

> It even handles that crazy case where you want to run on a specific day of the week. Does it handle the, in my opinion, not crazy case of running something every, say, 100 seconds?

borski 10y ago

Sadly, no. The minimum granularity is in minutes.

Bromskloss 10y ago
What about every 100 minutes?
- bahjoite 10y ago
  */100 * * * * echo "every 100 mins"
  - soneil 10y ago
    Have you tried this? Since minute only counts from 0-59, it's never divisible by 100. I have a similar problem with "every 2 days". */2 looks simple enough, but it fires on the 29th, miss 30th, fires on 31st, then fires the 1st. 3 times in 4 days isn't "every 2 days". Cron only works for periods which are evenly divisible into the calendar. "every 7 minutes" doesn't work because 60 isn't evenly divisible by 7. "every 5 hours" doesn't work (in that it'll match 8pm and midnight, which are only 4 hours apart), etc.
    - gkya 10y ago
      Well in cron "every two days" is more like "every second day of a month", and "ever 5 hours" like "every fifth hour of a day".
      - soneil 10y ago
        I guess that's what I was getting at. "every 100 minutes" doesn't work, because cron reads it as "every 100th minute of an hour".
    - bahjoite 10y ago
      You're right; thank you for pointing out my mistake. Every day's a school day.
    - jwilk 10y ago
      0 is divisible is by 100.
- jstimpfle 10y ago
  It's not designed for frequencies that don't align well with the partition of time in months, weeks, days, hours, minutes. But you probably can tweak your requirement slightly.
- edoceo 10y ago
  With fcron the line looks like @100 /do/my/thing.sh
  - pekeler 10y ago
    Is fcron stateful so that it remembers if the schedule started today at midnight, the first time it should run tomorrow is at 1am?
    - edoceo 10y ago
      As far as I can tell and if IIRC its across reboots too. I can't remember all the reasons I moved to fcron (10+ years ago) but the @# syntax was one factor
      - Bromskloss 10y ago
        > the @# syntax Watch your language!
- mappu 10y ago
  If you're really stuck with this requirement, and vixie cron is your only tool: */1 * * * * /usr/bin/bash -c '[[ $(( $(/usr/bin/date +%s) % 6000)) -eq 0 ]] && mycommand'