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diff --git a/man3p/asctime.3p b/man3p/asctime.3p new file mode 100644 index 000000000..5da1ee786 --- /dev/null +++ b/man3p/asctime.3p @@ -0,0 +1,140 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "ASCTIME" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" asctime +.SH NAME +asctime, asctime_r \- convert date and time to a string +.SH SYNOPSIS +.LP +\fB#include <time.h> +.br +.sp +char *asctime(const struct tm *\fP\fItimeptr\fP\fB); +.br +\fP +.LP +\fBchar *asctime_r(const struct tm *restrict\fP \fItm\fP\fB, char +*restrict\fP \fIbuf\fP\fB); +\fP +\fB +.br +\fP +.SH DESCRIPTION +.LP +For \fIasctime\fP(): 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 +IEEE\ Std\ 1003.1-2001 defers to the ISO\ C standard. +.LP +The \fIasctime\fP() function shall convert the broken-down time in +the structure pointed to by \fItimeptr\fP into a string in +the form: +.sp +.RS +.nf + +\fBSun Sep 16 01:03:52 1973\\n\\0 +\fP +.fi +.RE +.LP +using the equivalent of the following algorithm: +.sp +.RS +.nf + +\fBchar *asctime(const struct tm *timeptr) +{ + static char wday_name[7][3] = { + "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" + }; + static char mon_name[12][3] = { + "Jan", "Feb", "Mar", "Apr", "May", "Jun", + "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" + }; + static char result[26]; +.sp + + sprintf(result, "%.3s %.3s%3d %.2d:%.2d:%.2d %d\\n", + wday_name[timeptr->tm_wday], + mon_name[timeptr->tm_mon], + timeptr->tm_mday, timeptr->tm_hour, + timeptr->tm_min, timeptr->tm_sec, + 1900 + timeptr->tm_year); + return result; +} +\fP +.fi +.RE +.LP +The \fBtm\fP structure is defined in the \fI<time.h>\fP header. +.LP +The +\fIasctime\fP(), \fIctime\fP(), \fIgmtime\fP(), and +\fIlocaltime\fP() functions shall return values in one of two static +objects: a +broken-down time structure and an array of type \fBchar\fP. Execution +of any of the functions may overwrite the information +returned in either of these objects by any of the other functions. +.LP +The \fIasctime\fP() function need not be reentrant. A function that +is not required to be reentrant is not required to be +thread-safe. +.LP +The \fIasctime_r\fP() function shall convert the broken-down time +in the structure pointed to by \fItm\fP into a string (of the +same form as that returned by \fIasctime\fP()) that is placed in the +user-supplied buffer pointed to by \fIbuf\fP (which shall +contain at least 26 bytes) and then return \fIbuf\fP. +.SH RETURN VALUE +.LP +Upon successful completion, \fIasctime\fP() shall return a pointer +to the string. +.LP +Upon successful completion, \fIasctime_r\fP() shall return a pointer +to a character string containing the date and time. This +string is pointed to by the argument \fIbuf\fP. If the function is +unsuccessful, it shall return NULL. +.SH ERRORS +.LP +No errors are defined. +.LP +\fIThe following sections are informative.\fP +.SH EXAMPLES +.LP +None. +.SH APPLICATION USAGE +.LP +Values for the broken-down time structure can be obtained by calling +\fIgmtime\fP() or +\fIlocaltime\fP(). This function is included for compatibility with +older +implementations, and does not support localized date and time formats. +Applications should use \fIstrftime\fP() to achieve maximum portability. +.LP +The \fIasctime_r\fP() function is thread-safe and shall return values +in a user-supplied buffer instead of possibly using a +static data area that may be overwritten by each call. +.SH RATIONALE +.LP +None. +.SH FUTURE DIRECTIONS +.LP +None. +.SH SEE ALSO +.LP +\fIclock\fP() , \fIctime\fP() , \fIdifftime\fP() , \fIgmtime\fP() +, \fIlocaltime\fP() +, \fImktime\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 . |