I agree strptime()-style input format specification is badly missing in GNU date. Most other implementations support it:
- BSD with -f since 1997 (on FreeBSD at least; see also -v for adjustments) - ast-open's with -p since 2004 (also via standard getdate() DATEMSK) - busybox' with -D since 2006 - toybox' with -D since 2014 It's a regular occurrence on usenet or unix.stackexchange.com to see it mentioned that if you need to parse arbitrary date formats, you need to switch to another date implementation or use shell builtin facilities such as zsh's strftime builtin or ksh93's printf %T or resort to perl/ruby/python... Assaf Gordon did propose a patch in https://lists.gnu.org/archive/html/coreutils/2019-07/msg00053.html Both -p and -D are unassigned ATM AFAICT so could be used here. busybox and toybox mostly copied the GNU API, so it would make sense for GNU date to use -D for that so they don't become misaligned. While strptime() is not perfect, it's still better IMO than having to rely on the current -d behaviour which mostly accepts only US-English time specs and whose rules to parse times are not crystal clear. -- Stephane
