84 lines
1.4 KiB
Groff
84 lines
1.4 KiB
Groff
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.TH tai 3
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.SH NAME
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tai \- manipulate times with 1-second precision
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.SH SYNTAX
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.B #include <tai.h>
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double \fBtai_approx\fP(&\fIt\fR);
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int \fBtai_less\fP(&\fIa\fR,&\fIb\fR);
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.br
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void \fBtai_add\fP(&\fIt\fR,&\fIa\fR,&\fIb\fR);
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.br
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void \fBtai_sub\fP(&\fIt\fR,&\fIa\fR,&\fIb\fR);
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struct tai \fIt\fR;
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.br
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struct tai \fIa\fR;
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.br
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struct tai \fIb\fR;
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.SH DESCRIPTION
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A
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.B struct tai
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stores an integer between 0 inclusive and 2^64 exclusive.
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The format of
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.B struct tai
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is designed to speed up common operations;
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applications should not look inside
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.B struct tai\fR.
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A
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.B struct tai
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variable is commonly used to store
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a TAI64 label.
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Each TAI64 label refers to one second of real time.
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TAI64 labels span a period of
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hundreds of billions of years.
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See
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.B http://pobox.com/~djb/proto/tai64.txt
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for more information.
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A
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.B struct tai
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variable may also be used to store
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the numerical difference between two TAI64 labels.
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.SH ARITHMETIC
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.B tai_approx
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returns a double-precision approximation to
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.IR t .
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The result of
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.B tai_approx
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is always nonnegative.
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.B tai_less
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returns 1 if
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.I a
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is smaller than
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.IR b ,
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0 otherwise.
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.B tai_add
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adds
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.I a
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and
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.I b
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modulo 2^64
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and puts the result into
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.IR t .
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The inputs and outputs may overlap.
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.B tai_sub
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subtracts
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.I b
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from
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.I a
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modulo 2^64
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and puts the result into
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.IR t .
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The inputs and outputs may overlap.
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.SH "SEE ALSO"
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tai_now(3),
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tai_pack(3),
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taia(3),
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utc(3)
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