dysize(3) Library Functions Manual dysize(3)
NAME
dysize - get number of days for a given year
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#include <time.h>
int dysize(int year);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
dysize():
Since glibc 2.19:
_DEFAULT_SOURCE
glibc 2.19 and earlier:
_BSD_SOURCE || _SVID_SOURCE
DESCRIPTION
The function returns 365 for a normal year and 366 for a leap year. The
calculation for leap year is based on:
(year) %4 == 0 && ((year) %100 != 0 || (year) %400 == 0)
The formula is defined in the macro __isleap(year) also found in
<time.h>.
ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).
┌────────────────────────────────────────────┬───────────────┬─────────┐
│ Interface │ Attribute │ Value │
├────────────────────────────────────────────┼───────────────┼─────────┤
│ dysize() │ Thread safety │ MT-Safe │
└────────────────────────────────────────────┴───────────────┴─────────┘
STANDARDS
None.
HISTORY
SunOS 4.x.
This is a compatibility function only. Don't use it in new programs.
SEE ALSO
strftime(3)
Linux man-pages 6.9.1 2024-05-02 dysize(3)
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