The .SS field of the datetime argument of -t option can have range from 0 to 60
as per the 1003.1 2008 standard. POSIX has removed all mentions of double leap
seconds, therefore the allowed range of seconds is now [0,60].
Also, add an ENVIRONMENT section, as the interpretation of the datetime
argument in -t option depends on the TZ environment variable.
Add an xref for parsedate(3) in SEE ALSO.
ok wiz@
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