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diff --git a/man3/ctime.3 b/man3/ctime.3 deleted file mode 100644 index a6021f451..000000000 --- a/man3/ctime.3 +++ /dev/null @@ -1,414 +0,0 @@ -'\" t -.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk) -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" References consulted: -.\" Linux libc source code -.\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991) -.\" 386BSD man pages -.\" Modified Sat Jul 24 19:49:27 1993 by Rik Faith (faith@cs.unc.edu) -.\" Modified Fri Apr 26 12:38:55 MET DST 1996 by Martin Schulze (joey@linux.de) -.\" Modified 2001-11-13, aeb -.\" Modified 2001-12-13, joey, aeb -.\" Modified 2004-11-16, mtk -.\" -.TH ctime 3 (date) "Linux man-pages (unreleased)" -.SH NAME -asctime, ctime, gmtime, localtime, mktime, asctime_r, ctime_r, gmtime_r, -localtime_r \- transform date and time to broken-down time or ASCII -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <time.h> -.PP -.BI "char *asctime(const struct tm *" tm ); -.BI "char *asctime_r(const struct tm *restrict " tm , -.BI " char " buf "[restrict 26]);" -.PP -.BI "char *ctime(const time_t *" timep ); -.BI "char *ctime_r(const time_t *restrict " timep , -.BI " char " buf "[restrict 26]);" -.PP -.BI "struct tm *gmtime(const time_t *" timep ); -.BI "struct tm *gmtime_r(const time_t *restrict " timep , -.BI " struct tm *restrict " result ); -.PP -.BI "struct tm *localtime(const time_t *" timep ); -.BI "struct tm *localtime_r(const time_t *restrict " timep , -.BI " struct tm *restrict " result ); -.PP -.BI "time_t mktime(struct tm *" tm ); -.fi -.PP -.RS -4 -Feature Test Macro Requirements for glibc (see -.BR feature_test_macros (7)): -.RE -.PP -.BR asctime_r (), -.BR ctime_r (), -.BR gmtime_r (), -.BR localtime_r (): -.nf - _POSIX_C_SOURCE - || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE -.fi -.SH DESCRIPTION -The -.BR ctime (), -.BR gmtime (), -and -.BR localtime () -functions all take -an argument of data type \fItime_t\fP, which represents calendar time. -When interpreted as an absolute time value, it represents the number of -seconds elapsed since the Epoch, 1970-01-01 00:00:00 +0000 (UTC). -.PP -The -.BR asctime () -and -.BR mktime () -functions both take an argument -representing broken-down time, which is a representation -separated into year, month, day, and so on. -.PP -Broken-down time is stored in the structure -.IR tm , -described in -.BR tm (3type). -.PP -The call -.BI ctime( t ) -is equivalent to -.BI asctime(localtime( t )) \fR. -It converts the calendar time \fIt\fP into a -null-terminated string of the form -.PP -.in +4n -.EX -"Wed Jun 30 21:49:08 1993\en" -.EE -.in -.PP -The abbreviations for the days of the week are "Sun", "Mon", "Tue", "Wed", -"Thu", "Fri", and "Sat". -The abbreviations for the months are "Jan", -"Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", and -"Dec". -The return value points to a statically allocated string which -might be overwritten by subsequent calls to any of the date and time -functions. -The function also sets the external -variables \fItzname\fP, \fItimezone\fP, and \fIdaylight\fP (see -.BR tzset (3)) -with information about the current timezone. -The reentrant version -.BR ctime_r () -does the same, but stores the -string in a user-supplied buffer -which should have room for at least 26 bytes. -It need not -set \fItzname\fP, \fItimezone\fP, and \fIdaylight\fP. -.PP -The -.BR gmtime () -function converts the calendar time \fItimep\fP to -broken-down time representation, expressed in Coordinated Universal Time -(UTC). -It may return NULL when the year does not fit into an integer. -The return value points to a statically allocated struct which might be -overwritten by subsequent calls to any of the date and time functions. -The -.BR gmtime_r () -function does the same, but stores the data in a -user-supplied struct. -.PP -The -.BR localtime () -function converts the calendar time \fItimep\fP to -broken-down time representation, -expressed relative to the user's specified timezone. -The function acts as if it called -.BR tzset (3) -and sets the external variables \fItzname\fP with -information about the current timezone, \fItimezone\fP with the difference -between Coordinated Universal Time (UTC) and local standard time in -seconds, and \fIdaylight\fP to a nonzero value if daylight savings -time rules apply during some part of the year. -The return value points to a statically allocated struct which might be -overwritten by subsequent calls to any of the date and time functions. -The -.BR localtime_r () -function does the same, but stores the data in a -user-supplied struct. -It need not set \fItzname\fP, \fItimezone\fP, and \fIdaylight\fP. -.PP -The -.BR asctime () -function converts the broken-down time value -\fItm\fP into a null-terminated string with the same format as -.BR ctime (). -The return value points to a statically allocated string which might be -overwritten by subsequent calls to any of the date and time functions. -The -.BR asctime_r () -function does the same, but stores the string in -a user-supplied buffer which should have room for at least 26 bytes. -.PP -The -.BR mktime () -function converts a broken-down time structure, expressed -as local time, to calendar time representation. -The function ignores -the values supplied by the caller in the -.I tm_wday -and -.I tm_yday -fields. -The value specified in the -.I tm_isdst -field informs -.BR mktime () -whether or not daylight saving time (DST) -is in effect for the time supplied in the -.I tm -structure: -a positive value means DST is in effect; -zero means that DST is not in effect; -and a negative value means that -.BR mktime () -should (use timezone information and system databases to) -attempt to determine whether DST is in effect at the specified time. -.PP -The -.BR mktime () -function modifies the fields of the -.I tm -structure as follows: -.I tm_wday -and -.I tm_yday -are set to values determined from the contents of the other fields; -if structure members are outside their valid interval, they will be -normalized (so that, for example, 40 October is changed into 9 November); -.I tm_isdst -is set (regardless of its initial value) -to a positive value or to 0, respectively, -to indicate whether DST is or is not in effect at the specified time. -Calling -.BR mktime () -also sets the external variable \fItzname\fP with -information about the current timezone. -.PP -If the specified broken-down -time cannot be represented as calendar time (seconds since the Epoch), -.BR mktime () -returns -.I (time_t)\ \-1 -and does not alter the -members of the broken-down time structure. -.SH RETURN VALUE -On success, -.BR gmtime () -and -.BR localtime () -return a pointer to a -.IR "struct\ tm" . -.PP -On success, -.BR gmtime_r () -and -.BR localtime_r () -return the address of the structure pointed to by -.IR result . -.PP -On success, -.BR asctime () -and -.BR ctime () -return a pointer to a string. -.PP -On success, -.BR asctime_r () -and -.BR ctime_r () -return a pointer to the string pointed to by -.IR buf . -.PP -On success, -.BR mktime () -returns the calendar time (seconds since the Epoch), -expressed as a value of type -.IR time_t . -.PP -On error, -.BR mktime () -returns the value -.IR "(time_t)\ \-1" . -The remaining functions return NULL on error. -On error, -.I errno -is set 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). -.ad l -.nh -.TS -allbox; -lb lb lbx -l l l. -Interface Attribute Value -T{ -.BR asctime () -T} Thread safety T{ -MT-Unsafe race:asctime locale -T} -T{ -.BR asctime_r () -T} Thread safety T{ -MT-Safe locale -T} -T{ -.BR ctime () -T} Thread safety T{ -MT-Unsafe race:tmbuf -race:asctime env locale -T} -T{ -.BR ctime_r (), -.BR gmtime_r (), -.BR localtime_r (), -.BR mktime () -T} Thread safety T{ -MT-Safe env locale -T} -T{ -.BR gmtime (), -.BR localtime () -T} Thread safety T{ -MT-Unsafe race:tmbuf env locale -T} -.TE -.hy -.ad -.sp 1 -.SH VERSIONS -POSIX doesn't specify the parameters of -.BR ctime_r () -to be -.IR restrict ; -that is specific to glibc. -.PP -In many implementations, including glibc, a 0 in -.I tm_mday -is interpreted as meaning the last day of the preceding month. -.PP -According to POSIX.1-2001, -.BR localtime () -is required to behave as though -.BR tzset (3) -was called, while -.BR localtime_r () -does not have this requirement. -.\" See http://thread.gmane.org/gmane.comp.time.tz/2034/ -For portable code, -.BR tzset (3) -should be called before -.BR localtime_r (). -.SH STANDARDS -.TP -.BR asctime () -.TQ -.BR ctime () -.TQ -.BR gmtime () -.TQ -.BR localtime () -.TQ -.BR mktime () -C11, POSIX.1-2008. -.TP -.BR asctime_r () -.TQ -.BR ctime_r () -.TQ -.BR gmtime_r () -.TQ -.BR localtime_r () -POSIX.1-2008. -.SH HISTORY -.TP -.BR gmtime () -.TQ -.BR localtime () -.TQ -.BR mktime () -C89, POSIX.1-2001. -.TP -.BR asctime () -.TQ -.BR ctime () -C89, POSIX.1-2001. -Marked obsolete in POSIX.1-2008 (recommending -.BR strftime (3)). -.TP -.BR gmtime_r () -.TQ -.BR localtime_r () -POSIX.1-2001. -.TP -.BR asctime_r () -.TQ -.BR ctime_r () -POSIX.1-2001. -Marked obsolete in POSIX.1-2008 (recommending -.BR strftime (3)). -.SH NOTES -The four functions -.BR asctime (), -.BR ctime (), -.BR gmtime (), -and -.BR localtime () -return a pointer to static data and hence are not thread-safe. -The thread-safe versions, -.BR asctime_r (), -.BR ctime_r (), -.BR gmtime_r (), -and -.BR localtime_r (), -are specified by SUSv2. -.PP -POSIX.1-2001 says: -"The -.BR asctime (), -.BR ctime (), -.BR gmtime (), -and -.BR localtime () -functions shall return values in one of two static objects: -a broken-down time structure and an array of type -.IR char . -Execution of any of the functions may overwrite the information returned -in either of these objects by any of the other functions." -This can occur in the glibc implementation. -.SH SEE ALSO -.BR date (1), -.BR gettimeofday (2), -.BR time (2), -.BR utime (2), -.BR clock (3), -.BR difftime (3), -.BR strftime (3), -.BR strptime (3), -.BR timegm (3), -.BR tzset (3), -.BR time (7) |