62 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			Groff
		
	
	
	
	
	
		
		
			
		
	
	
			62 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			Groff
		
	
	
	
	
	
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								.TH caltime 3
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								.SH NAME
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								caltime_tai \- convert calendar dates and times
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								.SH SYNTAX
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								.B #include <caltime.h>
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								.br
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								.B #include <tai.h>
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								void \fBcaltime_tai\fP(&\fIct\fR,&\fIt\fR);
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								.br
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								void \fBcaltime_utc\fP(&\fIct\fR,&\fIt\fR,&\fIweekday\fR,&\fIyearday\fR);
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								struct caltime \fIct\fR;
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								.br
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								struct tai \fIt\fR;
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								.br
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								int *\fIweekday\fR;
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								.br
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								int *\fIyearday\fR;
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								.SH DESCRIPTION
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								.B caltime_tai
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								reads a date, time, and UTC offset from
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								.IR ct .
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								It puts the corresponding TAI64 label into
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								.IR t .
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								.B caltime_utc
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								reads a TAI64 label from
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								.IR t .
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								It puts the corresponding date and time into
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								.IR ct ,
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								with UTC offset 0.
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								.B caltime_utc
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								fills in
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								.I weekday
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								and
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								.I yearday
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								the same way as
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								.BR caldate_frommjd .
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								.SH LIMITATIONS
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								The sequence of TAI64 labels has been determined
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								for the next few hundred billion years.
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								The same is not true, however, for
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								calendar dates and times.
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								New leap seconds are added every year or two,
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								as discussed in
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								.BR leapsecs (3);
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								and the Gregorian calendar will change in a few thousand years,
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								as discussed in
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								.BR caldate_mjd (3).
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								This means that
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								.B caltime_tai
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								and
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								.B caltime_utc
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								are not useful for dates far in the future.
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								.SH "SEE ALSO"
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								caldate_mjd(3),
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								caltime(3),
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								tai(3),
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								leapsecs(3)
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