crontab 4th Tuesday of month

[Michael Schwendt]

On Sat, 28 Jul 2012 12:03:09 +0100, Frank Murphy wrote:

> 15 18 22-28 * 2 /command
> 
> I thought the last tuesday would be covered by above.
> But it has run everyday since 22nd.
> 
> Have googled a bit:
> http://hintsforums.macworld.com/showthread.php?t=25110
> plus other crontab pages.
> 
> http://hintsforums.macworld.com/member.php?s=2584787478dc5ab0791da9ba8d650aa5&u=28924
> 15 18 22-28 * * test 'date +\%a' != Tue || /command
> Am uncertain if above would work ootb.
> 
> man crontab (22 September 2010) doesn't shed light on this.

 From the manual:

      Note: The day of a command's execution can be specified in the  follow‐
      ing two fields — 'day of month', and 'day of week'.  If both fields are
      restricted (i.e., do not contain the "*" character), the  command  will
      be run when either field matches the current time.  For example,
      "30  4  1,15 * 5" would cause a command to be run at 4:30 am on the 1st
      and 15th of each month, plus every Friday.

That matches your example.