When I need to look at what day a date is on, I typically open the Calendar app. But sometimes I’m in the middle of a task in the command line and don’t want to do so. Luckily, there’s a cal binary in OS X. To use cal, simply invoke it and ask for a julian calendar using the -j option:
cal -j
Which outputs a calendar view:
March 2016
Su Mo Tu We Th Fr Sa
61 62 63 64 65
66 67 68 69 70 71 72
73 74 75 76 77 78 79
80 81 82 83 84 85 86
87 88 89 90 91
The days you see above are numbered as the day in order in that year. To see the full year, use -jy:
cal -jy
To just see one month, use the -m followed by the number of the month. So to see July:
cal -j -m 7
To see all of 2018, use the -y and the year:
cal -j -y 2018
To see the dy of the month, we’ll use ncal, which also shows which day of the week each day fall on:
ncal -J
The output would be as follows:
March 2016
Mo 1 8 15 22 29
Tu 2 9 16 23 30
We 3 10 17 24 31
Th 4 11 18 25
Fr 5 12 19 26
Sa 6 13 20 27
Su 7 14 21 28
When I’m scripting, especially with outputting to logger, I’ll usually use date. But cal and ncal are nice little doohickeys for quickly finding days and dates and the such. Happy calendaring!
