yest
is a great tool which allows user to do some complex date manipulations by employing ab easy to understand syntax. It is not a competitor to a date command, rather it is a handy tool which has some features you may not find in date command. Name of the yest command is derived from its default no argument output which is yesterday’s date.
You can download a latest version of yest from SourceForge:
https://sourceforge.net/projects/yest/files/yest/2.7.0.4/yest-2.7.0.4.c/download
Compile:
$ gcc yest-2.7.0.4.c -o yest
and add it to your path:
# cp yest /usr/local/bin
Here are some examples of yest usage:
What day was on 6.8.1938
$ yest 1938-08-06 +0 %A Saturday
How many days are in a current month:
$ yest +0 %L 31
Show epoch time to current date:
$ yest +0 %s 1301044056
Is daylight savings time active?, 1-yes 0-no:
$ yest +0 %q 1
Show my time zone:
$ yest %Z EST
Add 45 days to 28.12.1923
$ yest 1923-12-28 +45 11/02/1924
Subtract 300 days from 28.12.1923:
$ yest 1923-12-28 -300 03/03/1923
Show date 1000 days back:
$ yest -1000d %f Saturday, June 28th, 2008 - 07:39:49 pm
Show date 1000 hours in the future from now:
$ yest +1000h %f Friday, May 6th, 2011 - 11:41:32 am
Show usage:
$ yest --help