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diff --git a/man-pages-posix-2013/man3p/mktime.3p b/man-pages-posix-2013/man3p/mktime.3p new file mode 100644 index 0000000..f8f673a --- /dev/null +++ b/man-pages-posix-2013/man3p/mktime.3p @@ -0,0 +1,175 @@ +'\" et +.TH MKTIME "3P" 2013 "IEEE/The Open Group" "POSIX Programmer's Manual" +.SH PROLOG +This manual page is part of the POSIX Programmer's Manual. +The Linux implementation of this interface may differ (consult +the corresponding Linux manual page for details of Linux behavior), +or the interface may not be implemented on Linux. + +.SH NAME +mktime +\(em convert broken-down time into time since the Epoch +.SH SYNOPSIS +.LP +.nf +#include <time.h> +.P +time_t mktime(struct tm *\fItimeptr\fP); +.fi +.SH DESCRIPTION +The functionality described on this reference page is aligned with the +ISO\ C standard. Any conflict between the requirements described here and the +ISO\ C standard is unintentional. This volume of POSIX.1\(hy2008 defers to the ISO\ C standard. +.P +The +\fImktime\fR() +function shall convert the broken-down time, expressed as local time, +in the structure pointed to by +.IR timeptr , +into a time since the Epoch value with the same encoding as that of the +values returned by +\fItime\fR(). +The original values of the +.IR tm_wday +and +.IR tm_yday +components of the structure are ignored, and the original values +of the other components are not restricted to the ranges +described in +.IR <time.h> . +.P +A positive or 0 value for +.IR tm_isdst +shall cause +\fImktime\fR() +to presume initially that Daylight Savings Time, respectively, is or is +not in effect for the specified time. A negative value for +.IR tm_isdst +shall cause +\fImktime\fR() +to attempt to determine whether Daylight Savings Time is in effect for +the specified time. +.P +Local timezone information shall be set as though +\fImktime\fR() +called +\fItzset\fR(). +.P +The relationship between the +.BR tm +structure (defined in the +.IR <time.h> +header) and the time in seconds since the Epoch is that the result +shall be as specified in the expression given in the definition of +seconds since the Epoch (see the Base Definitions volume of POSIX.1\(hy2008, +.IR "Section 4.15" ", " "Seconds Since the Epoch") +corrected for timezone and any seasonal time adjustments, where the +names in the structure and in the expression correspond. +.P +Upon successful completion, the values of the +.IR tm_wday +and +.IR tm_yday +components of the structure shall be set appropriately, and the other +components are set to represent the specified time since the Epoch, but +with their values forced to the ranges indicated in the +.IR <time.h> +entry; the final value of +.IR tm_mday +shall not be set until +.IR tm_mon +and +.IR tm_year +are determined. +.SH "RETURN VALUE" +The +\fImktime\fR() +function shall return the specified time since the Epoch encoded as +a value of type +.BR time_t . +If the time since the Epoch cannot be represented, the function shall +return the value (\fBtime_t\fP)\(mi1 +and set +.IR errno +to indicate the error. +.SH ERRORS +The +\fImktime\fR() +function shall fail if: +.TP +.BR EOVERFLOW +The result cannot be represented. +.LP +.IR "The following sections are informative." +.SH "EXAMPLES" +What day of the week is July 4, 2001? +.sp +.RS 4 +.nf +\fB +#include <stdio.h> +#include <time.h> +.P +struct tm time_str; +.P +char daybuf[20]; +.P +int main(void) +{ + time_str.tm_year = 2001 \(em 1900; + time_str.tm_mon = 7 \(em 1; + time_str.tm_mday = 4; + time_str.tm_hour = 0; + time_str.tm_min = 0; + time_str.tm_sec = 1; + time_str.tm_isdst = \(mi1; + if (mktime(&time_str) == -1) + (void)puts("-unknown-"); + else { + (void)strftime(daybuf, sizeof(daybuf), "%A", &time_str); + (void)puts(daybuf); + } + return 0; +} +.fi \fR +.P +.RE +.SH "APPLICATION USAGE" +None. +.SH RATIONALE +None. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "\fIasctime\fR\^(\|)", +.IR "\fIclock\fR\^(\|)", +.IR "\fIctime\fR\^(\|)", +.IR "\fIdifftime\fR\^(\|)", +.IR "\fIgmtime\fR\^(\|)", +.IR "\fIlocaltime\fR\^(\|)", +.IR "\fIstrftime\fR\^(\|)", +.IR "\fIstrptime\fR\^(\|)", +.IR "\fItime\fR\^(\|)", +.IR "\fItzset\fR\^(\|)", +.IR "\fIutime\fR\^(\|)" +.P +The Base Definitions volume of POSIX.1\(hy2008, +.IR "Section 4.15" ", " "Seconds Since the Epoch", +.IR "\fB<time.h>\fP" +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, Copyright (C) 2013 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. +(This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the +event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.unix.org/online.html . + +Any typographical or formatting errors that appear +in this page are most likely +to have been introduced during the conversion of the source files to +man page format. To report such errors, see +https://www.kernel.org/doc/man-pages/reporting_bugs.html . |