G'day JohnGG,
++
Upon reading the OP, I immediately thought of Time::Piece;
then, after scrolling through the posts, I saw you'd used this already.
If I may, some minor improvements:
-
Instead of decrementing $tp in two statements, you can do that in one: "$tp -= 2 * ONE_HOUR".
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Your output has a slightly different format to the OP's input:
comma after day and introduced timezone.
You can mostly fix that by using the same date format for the input and output.
Update: On rereading, I also see the month name and day are swapped as are the time and year.
The suggested fix handles both of those cases also.
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If the leading zero on the month
nameday is a problem for the OP, you can fix that with sprintf.
I added a "$tp += 6 * ONE_DAY" to test that.
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Checking `man strptime` on my Cygwin platform, I see %d gives a two-digit string,
padded with a zero for a single-digit month day.
I couldn't find a format for that which doesn't pad with a zero.
Assuming I didn't simply miss it, if one exists on another OS, it may not be portable.
Here's the updated code:
my $date = q{Sat Jun 4 22:47:31 2022};
my $fmt_t = q{%a %b %d %T %Y};
my $fmt_s = q{%s %s %2d %s %d};
my $tp = Time::Piece->strptime($date, $fmt_t);
$tp -= 2 * ONE_HOUR;
say sprintf $fmt_s, split q{ }, $tp->strftime($fmt_t);
$tp += 6 * ONE_DAY;
say sprintf $fmt_s, split q{ }, $tp->strftime($fmt_t);
which outputs:
Sat Jun 4 20:47:31 2022
Fri Jun 10 20:47:31 2022