timelocal (3) - Linux Man Pages
timelocal: inverses of gmtime and localtime
timegm, timelocal - inverses of gmtime and localtime
#include <time.h> time_t timelocal(struct tm *tm); time_t timegm(struct tm *tm);Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
are the inverses of
Both functions take a broken-down time and convert it to calendar time
(seconds since the Epoch, 1970-01-01 00:00:00 +0000, UTC).
The difference between the two functions is that
takes the local timezone into account when doing the conversion, while
takes the input value to be Coordinated Universal Time (UTC).
these functions return the calendar time (seconds since the Epoch),
expressed as a value of type
On error, they return the value
to indicate the cause of the error.
For an explanation of the terms used in this section, see
Interface Attribute Value
Thread safety MT-Safe env locale
These functions are nonstandard GNU extensions
that are also present on the BSDs.
Avoid their use.
function is equivalent to the POSIX standard function
There is no reason to ever use it.
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