‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐ On Friday, August 20, 2021 8:00 PM, Kerin Millar <k...@plushkava.net> wrote:
> On Fri, 20 Aug 2021 19:28:25 +0000 > hancooper via Bug reports for the GNU Bourne Again SHell bug-bash@gnu.org > wrote: > > > I am using EPOCHREALTIME and then computing the corresponding human > > readable form, that can handle > > changes in locale > > now=$EPOCHREALTIME > > printf -v second '%(%S)T.%s' "${now%[^[:digit:]]}" "${now#[^[:digit:]]}" > > printf -v minute '%(%M)T' "${now%[^[:digit:]]}" > > printf -v hour '%(%H)T' "${now%[^[:digit:]]}"Incidentally, [![:digit:]] > > does not work there, you need to use the POSIX-specified caret (^) instead > > of an > > exclamation mark when using character classes. I'm not sure if this is > > intentional or a bug in bash; man > > page doesn't seem to mention it. > > "If an open bracket introduces a bracket expression as in XBD RE Bracket > Expression, [...] the <exclamation-mark> character ( '!' ) shall replace the > <circumflex> character ( '^' ) in its role in a non-matching list in the > regular expression notation." > > So says POSIX on the matter of pattern matching notation. In other words, > only the exclamation-mark is POSIX-specified, although bash happens to > tolerate the use of a circumflex, in which case it should behave in the exact > same way. Are you able to show a concrete example of one behaving differently > from the other? I could do with some help separating the integer and the fractional part from a floating point number, particularly for the situation where the number starts with a period. t="13.357713" # integer part of time interval ts="${t%%[![:digit:]]+([:digit:])}" # remove longest match from back # 13.877597, remove .877597 # fractional part of time interval fr="${t##*([:digit:])[![:digit:]]}" # remove longest match from front # 13.877597, remove 13.