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diff --git a/man3p/mktime.3p b/man3p/mktime.3p new file mode 100644 index 000000000..5b8647c86 --- /dev/null +++ b/man3p/mktime.3p @@ -0,0 +1,123 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "MKTIME" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" mktime +.SH NAME +mktime \- convert broken-down time into time since the Epoch +.SH SYNOPSIS +.LP +\fB#include <time.h> +.br +.sp +time_t mktime(struct tm *\fP\fItimeptr\fP\fB); +.br +\fP +.SH DESCRIPTION +.LP +The \fImktime\fP() function shall convert the broken-down time, expressed +as local time, in the structure pointed to by +\fItimeptr\fP, into a time since the Epoch value with the same encoding +as that of the values returned by \fItime\fP(). The original values +of the \fItm_wday\fP and \fItm_yday\fP components of the +structure are ignored, and the original values of the other components +are not restricted to the ranges described in \fI<time.h>\fP. +.LP +A +positive or 0 value for \fItm_isdst\fP shall cause \fImktime\fP() +to presume initially that Daylight Savings Time, respectively, +is or is not in effect for the specified time. A negative value for +\fItm_isdst\fP shall cause \fImktime\fP() to attempt to +determine whether Daylight Savings Time is in effect for the specified +time. +.LP +Local timezone information shall be set as though \fImktime\fP() called +\fItzset\fP(). +.LP +The relationship between the \fBtm\fP structure (defined in the \fI<time.h>\fP +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 IEEE\ Std\ 1003.1-2001, +Section 4.14, Seconds Since the Epoch) corrected for timezone and +any seasonal time +adjustments, where the names in the structure and in the expression +correspond. +.LP +Upon successful completion, the values of the \fItm_wday\fP and \fItm_yday\fP +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 \fI<time.h>\fP entry; the final value +of \fItm_mday\fP +shall not be set until \fItm_mon\fP and \fItm_year\fP are determined. +.SH RETURN VALUE +.LP +The \fImktime\fP() function shall return the specified time since +the Epoch encoded as a value of type \fBtime_t\fP. If the +time since the Epoch cannot be represented, the function shall return +the value (\fBtime_t\fP)-1. +.SH ERRORS +.LP +No errors are defined. +.LP +\fIThe following sections are informative.\fP +.SH EXAMPLES +.LP +What day of the week is July 4, 2001? +.sp +.RS +.nf + +\fB#include <stdio.h> +#include <time.h> +.sp + +struct tm time_str; +.sp + +char daybuf[20]; +.sp + +int main(void) +{ + time_str.tm_year = 2001 - 1900; + time_str.tm_mon = 7 - 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 = -1; + if (mktime(&time_str) == -1) + (void)puts("-unknown-"); + else { + (void)strftime(daybuf, sizeof(daybuf), "%A", &time_str); + (void)puts(daybuf); + } + return 0; +} +\fP +.fi +.RE +.SH APPLICATION USAGE +.LP +None. +.SH RATIONALE +.LP +None. +.SH FUTURE DIRECTIONS +.LP +None. +.SH SEE ALSO +.LP +\fIasctime\fP() , \fIclock\fP() , \fIctime\fP() +, \fIdifftime\fP() , \fIgmtime\fP() , \fIlocaltime\fP() , \fIstrftime\fP() +, \fIstrptime\fP() , \fItime\fP() , \fIutime\fP() , the Base +Definitions volume of IEEE\ Std\ 1003.1-2001, \fI<time.h>\fP +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. 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.opengroup.org/unix/online.html . |