bug#35078: Possible bug in the date command, to do with %p

[Assaf Gordon]

tags 35078 notabug
close 35078
stop

Hello,

On 2019-04-02 2:14 a.m., Nicholas Joll wrote:
> The manual for 'date' includes this:
>         %p     locale's equivalent of either AM or PM; blank if not known
>         %P     like %p, but lower case
>
> But on my system:
>
>       $  date +%p
>      am
>      $  date +%P
>      am
>
> That is: it seems impossible to get a capitalised 'AM' or 'PM'.
>
> Might this be a problem with my locale? Here is how my locale is set:
>
>      $  locale
>      LANG=en_GB.UTF-8

Exactly as you suspected: it is due to your locale.

Note the wording:
  "locale's *equivalent* of either AM or PM"
So not the exact strings AM or PM, but what your locate uses.

In C/POSIX, these are indeed upper/lower case:

  $ LC_ALL=C date +"%p %P"
  AM am

Same for Canada:

  $ LC_ALL=en_CA.UTF-8 date +"%p %P"
  AM am

But not for Great Britain:

  $ LC_ALL=en_GB.UTF-8 date +"%p %P"
  am am

Also note that these are blank in many other locales:

  $ LC_ALL=ru_RU.utf8 date +"=%p=%P="
  ===



I'm making this as "not a bug", but discussion can continue by
replying to this thread.

-assaf