1DIFFTIME(3) Linux Programmer's Manual DIFFTIME(3)
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6 difftime - calculate time difference
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9 #include <time.h>
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11 double difftime(time_t time1, time_t time0);
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14 The difftime() function returns the number of seconds elapsed between
15 time time1 and time time0, represented as a double. The two times are
16 specified in calendar time, which represents the time elapsed since the
17 Epoch (00:00:00 on January 1, 1970, Coordinated Universal Time (UTC)).
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20 SVr4, 4.3BSD, C89, C99.
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23 On a POSIX system, time_t is an arithmetic type, and one could just
24 define
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26 #define difftime(t1,t0) (double)(t1 - t0)
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28 when the possible overflow in the subtraction is not a concern. On
29 other systems, the data type time_t might use some other encoding where
30 subtraction doesn't work directly.
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33 date(1), gettimeofday(2), time(2), ctime(3), gmtime(3), localtime(3)
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36 This page is part of release 3.22 of the Linux man-pages project. A
37 description of the project, and information about reporting bugs, can
38 be found at http://www.kernel.org/doc/man-pages/.
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42GNU 2002-02-28 DIFFTIME(3)