Re: can strftime show 'p.m.' instead of 'PM'?

["Benjamin R. Haskell" <zsh@benizi.com>]

On Sat, 28 Apr 2012, TJ Luoma wrote:

>
> Before I begin, I should say that I realize this may (seem to) be 
> extremely picayune, but it consistently annoys me. Judge me as you 
> will :-)
>
> `man strftime` says this:
>
>     %p    is replaced by national representation of either "ante meridiem" (a.m.)  or "post meridiem" (p.m.)  as appropriate.
>
>     %F    is equivalent to ``%Y-%m-%d''.
>
>     %r    is equivalent to ``%I:%M:%S %p''.

My `man strftime` lists:

%p     Either "AM" or "PM" according to the given time value, or the 
corresponding strings for the current locale.  Noon is treated as "PM" 
and midnight as "AM".

%P     Like %p but in lowercase: "am" or "pm" or a corresponding string 
for the current locale. (GNU)

AFAIK, the strftime provided by zsh/datetime just passes its format 
string to the C library function.  (So, right now, %p and %P get me 'PM' 
and 'pm', respectively.)


> However when I do this in zsh
>
> $ strftime "%F %r" "$EPOCHSECONDS"
>
> I get this:
>
> 2012-04-28 02:50:24 PM
>
> Ideally I would like "PM" to be "p.m." but I'd probably settle for "pm"
>
> I tried using '%P' instead of '%p' (thinking that might invert the case) but that just gave me a literal 'P' instead.
>
> I realize that I could use:
>
> strftime "%F %r" "$EPOCHSECONDS" | tr '[A-Z]' '[a-z]'
>
> or even
>
> strftime "%F %r" "$EPOCHSECONDS" | sed 's#AM#a.m#g; s#pPM#p.m.#g'
>
> but I wondered if there was a better (more efficient) way.

Since it's system-dependent, you're probably better off munging it 
yourself.  But if you're extremely worried about efficiency, you don't 
need to pipe to `tr` or `sed` (so you can avoid launching an external 
process):

print -r - ${${${:-"$(strftime "%F %r" "$EPOCHSECONDS")"}/AM/a.m.}/PM/p.m.}

-- 
Best,
Ben