1OPENSSL_GMTIME(3ossl)               OpenSSL              OPENSSL_GMTIME(3ossl)
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NAME

6       OPENSSL_gmtime, OPENSSL_gmtime_adj, OPENSSL_gmtime_diff -
7       platform-agnostic OpenSSL time routines
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SYNOPSIS

10        #include <openssl/crypto.h>
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12        struct tm *OPENSSL_gmtime(const time_t *timer, struct tm *result);
13        int OPENSSL_gmtime_adj(struct tm *tm, int offset_day, long offset_sec);
14        int OPENSSL_gmtime_diff(int *pday, int *psec,
15                               const struct tm *from, const struct tm *to);
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DESCRIPTION

18       OPENSSL_gmtime() returns the UTC time specified by timer into the
19       provided result argument.
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21       OPENSSL_gmtime_adj() adds the offsets in offset_day and offset_sec to
22       tm.
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24       OPENSSL_gmtime_diff() calculates the difference between from and to.
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NOTES

27       It is an error to call OPENSSL_gmtime() with result equal to NULL. The
28       contents of the time_t given by timer are stored into the result.
29       Calling with timer equal to NULL means use the current time.
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31       OPENSSL_gmtime_adj() converts tm into a days and seconds value, adds
32       the offsets, then converts back into a struct tm specified by tm. Leap
33       seconds are not considered.
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35       OPENSSL_gmtime_diff() calculates the difference between the two struct
36       tm structures from and to. The difference in days is placed into *pday,
37       the remaining seconds are placed to *psec. The value in *psec will be
38       less than the number of seconds per day (3600). Leap seconds are not
39       considered.
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RETURN VALUES

42       OPENSSL_gmtime() returns NULL on error, or result on success.
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44       OPENSSL_gmtime_adj() and OPENSSL_gmtime_diff() return 0 on error, and 1
45       on success.
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HISTORY

48       OPENSSL_gmtime(), OPENSSL_gmtime_adj() and OPENSSL_gmtime_diff() have
49       been in OpenSSL since 1.0.0.
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52       Copyright 2022 The OpenSSL Project Authors. All Rights Reserved.
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54       Licensed under the Apache License 2.0 (the "License").  You may not use
55       this file except in compliance with the License.  You can obtain a copy
56       in the file LICENSE in the source distribution or at
57       <https://www.openssl.org/source/license.html>.
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613.1.1                             2023-08-31             OPENSSL_GMTIME(3ossl)
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