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diff --git a/man3/timegm.3 b/man3/timegm.3 new file mode 100644 index 0000000..659fc8a --- /dev/null +++ b/man3/timegm.3 @@ -0,0 +1,93 @@ +'\" t +.\" Copyright (C) 2001 Andries Brouwer <aeb@cwi.nl> +.\" +.\" SPDX-License-Identifier: Linux-man-pages-copyleft +.\" +.TH timegm 3 2023-07-20 "Linux man-pages 6.05.01" +.SH NAME +timegm, timelocal \- inverses of gmtime and localtime +.SH LIBRARY +Standard C library +.RI ( libc ", " \-lc ) +.SH SYNOPSIS +.nf +.B #include <time.h> +.PP +.BI "[[deprecated]] time_t timelocal(struct tm *" tm ); +.BI "time_t timegm(struct tm *" tm ); +.PP +.fi +.RS -4 +Feature Test Macro Requirements for glibc (see +.BR feature_test_macros (7)): +.RE +.PP +.BR timelocal (), +.BR timegm (): +.nf + Since glibc 2.19: + _DEFAULT_SOURCE + glibc 2.19 and earlier: + _BSD_SOURCE || _SVID_SOURCE +.fi +.SH DESCRIPTION +The functions +.BR timelocal () +and +.BR timegm () +are the inverses of +.BR localtime (3) +and +.BR gmtime (3). +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 +.BR timelocal () +takes the local timezone into account when doing the conversion, while +.BR timegm () +takes the input value to be Coordinated Universal Time (UTC). +.SH RETURN VALUE +On success, +these functions return the calendar time (seconds since the Epoch), +expressed as a value of type +.IR time_t . +On error, they return the value +.I (time_t)\ \-1 +and set +.I errno +to indicate the error. +.SH ERRORS +.TP +.B EOVERFLOW +The result cannot be represented. +.SH ATTRIBUTES +For an explanation of the terms used in this section, see +.BR attributes (7). +.TS +allbox; +lbx lb lb +l l l. +Interface Attribute Value +T{ +.na +.nh +.BR timelocal (), +.BR timegm () +T} Thread safety MT-Safe env locale +.TE +.sp 1 +.SH STANDARDS +BSD. +.SH HISTORY +GNU, BSD. +.PP +The +.BR timelocal () +function is equivalent to the POSIX standard function +.BR mktime (3). +There is no reason to ever use it. +.SH SEE ALSO +.BR gmtime (3), +.BR localtime (3), +.BR mktime (3), +.BR tzset (3) |