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diff --git a/man2/gettimeofday.2 b/man2/gettimeofday.2 deleted file mode 100644 index 9d134fa49..000000000 --- a/man2/gettimeofday.2 +++ /dev/null @@ -1,285 +0,0 @@ -.\" Copyright (c) 1992 Drew Eckhardt (drew@cs.colorado.edu), March 28, 1992 -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" Modified by Michael Haardt (michael@moria.de) -.\" Modified 1993-07-23 by Rik Faith (faith@cs.unc.edu) -.\" Modified 1994-08-21 by Michael Chastain (mec@shell.portal.com): -.\" Fixed necessary '#include' lines. -.\" Modified 1995-04-15 by Michael Chastain (mec@shell.portal.com): -.\" Added reference to adjtimex. -.\" Removed some nonsense lines pointed out by Urs Thuermann, -.\" (urs@isnogud.escape.de), aeb, 950722. -.\" Modified 1997-01-14 by Austin Donnelly (and1000@debian.org): -.\" Added return values section, and bit on EFAULT -.\" Added clarification on timezone, aeb, 971210. -.\" Removed "#include <unistd.h>", aeb, 010316. -.\" Modified, 2004-05-27 by Michael Kerrisk <mtk.manpages@gmail.com> -.\" Added notes on capability requirement. -.\" -.TH gettimeofday 2 (date) "Linux man-pages (unreleased)" -.SH NAME -gettimeofday, settimeofday \- get / set time -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <sys/time.h> -.PP -.BI "int gettimeofday(struct timeval *restrict " tv , -.BI " struct timezone *_Nullable restrict " tz ); -.BI "int settimeofday(const struct timeval *" tv , -.BI " const struct timezone *_Nullable " tz ); -.fi -.PP -.RS -4 -Feature Test Macro Requirements for glibc (see -.BR feature_test_macros (7)): -.RE -.PP -.BR settimeofday (): -.nf - Since glibc 2.19: - _DEFAULT_SOURCE - glibc 2.19 and earlier: - _BSD_SOURCE -.fi -.SH DESCRIPTION -The functions -.BR gettimeofday () -and -.BR settimeofday () -can get and set the time as well as a timezone. -.PP -The -.I tv -argument is a -.I struct timeval -(as specified in -.IR <sys/time.h> ): -.PP -.in +4n -.EX -struct timeval { - time_t tv_sec; /* seconds */ - suseconds_t tv_usec; /* microseconds */ -}; -.EE -.in -.PP -and gives the number of seconds and microseconds since the Epoch (see -.BR time (2)). -.PP -The -.I tz -argument is a -.IR "struct timezone" : -.PP -.in +4n -.EX -struct timezone { - int tz_minuteswest; /* minutes west of Greenwich */ - int tz_dsttime; /* type of DST correction */ -}; -.EE -.in -.PP -If either -.I tv -or -.I tz -is NULL, the corresponding structure is not set or returned. -.\" FIXME . The compilation warning looks to be going away in glibc 2.17 -.\" see glibc commit 4b7634a5e03b0da6f8875de9d3f74c1cf6f2a6e8 -(However, compilation warnings will result if -.I tv -is NULL.) -.\" The following is covered under EPERM below: -.\" .PP -.\" Only the superuser may use -.\" .BR settimeofday (). -.PP -The use of the -.I timezone -structure is obsolete; the -.I tz -argument should normally be specified as NULL. -(See NOTES below.) -.PP -Under Linux, there are some peculiar "warp clock" semantics associated -with the -.BR settimeofday () -system call if on the very first call (after booting) -that has a non-NULL -.I tz -argument, the -.I tv -argument is NULL and the -.I tz_minuteswest -field is nonzero. -(The -.I tz_dsttime -field should be zero for this case.) -In such a case it is assumed that the CMOS clock -is on local time, and that it has to be incremented by this amount -to get UTC system time. -No doubt it is a bad idea to use this feature. -.SH RETURN VALUE -.BR gettimeofday () -and -.BR settimeofday () -return 0 for success. -On error, \-1 is returned and -.I errno -is set to indicate the error. -.SH ERRORS -.TP -.B EFAULT -One of -.I tv -or -.I tz -pointed outside the accessible address space. -.TP -.B EINVAL -.RB ( settimeofday ()): -.I timezone -is invalid. -.TP -.B EINVAL -.RB ( settimeofday ()): -.I tv.tv_sec -is negative or -.I tv.tv_usec -is outside the range [0, 999,999]. -.TP -.BR EINVAL " (since Linux 4.3)" -.\" commit e1d7ba8735551ed79c7a0463a042353574b96da3 -.RB ( settimeofday ()): -An attempt was made to set the time to a value less than -the current value of the -.B CLOCK_MONOTONIC -clock (see -.BR clock_gettime (2)). -.TP -.B EPERM -The calling process has insufficient privilege to call -.BR settimeofday (); -under Linux the -.B CAP_SYS_TIME -capability is required. -.SH VERSIONS -.SS C library/kernel differences -On some architectures, an implementation of -.BR gettimeofday () -is provided in the -.BR vdso (7). -.SH STANDARDS -.TP -.BR gettimeofday () -POSIX.1-2008 (obsolete). -.TP -.BR settimeofday () -None. -.SH HISTORY -SVr4, 4.3BSD. -POSIX.1-2001 describes -.BR gettimeofday () -but not -.BR settimeofday (). -POSIX.1-2008 marks -.BR gettimeofday () -as obsolete, recommending the use of -.BR clock_gettime (2) -instead. -.PP -Traditionally, the fields of -.I struct timeval -were of type -.IR long . -.\" -.SS The tz_dsttime field -On a non-Linux kernel, with glibc, the -.I tz_dsttime -field of -.I struct timezone -will be set to a nonzero value by -.BR gettimeofday () -if the current timezone has ever had or will have a daylight saving -rule applied. -In this sense it exactly mirrors the meaning of -.BR daylight (3) -for the current zone. -On Linux, with glibc, the setting of the -.I tz_dsttime -field of -.I struct timezone -has never been used by -.BR settimeofday () -or -.BR gettimeofday (). -.\" it has not -.\" been and will not be supported by libc or glibc. -.\" Each and every occurrence of this field in the kernel source -.\" (other than the declaration) is a bug. -Thus, the following is purely of historical interest. -.PP -On old systems, the field -.I tz_dsttime -contains a symbolic constant (values are given below) -that indicates in which part of the year Daylight Saving Time -is in force. -(Note: this value is constant throughout the year: -it does not indicate that DST is in force, it just selects an -algorithm.) -The daylight saving time algorithms defined are as follows: -.PP -.in +4n -.EX -\fBDST_NONE\fP /* not on DST */ -\fBDST_USA\fP /* USA style DST */ -\fBDST_AUST\fP /* Australian style DST */ -\fBDST_WET\fP /* Western European DST */ -\fBDST_MET\fP /* Middle European DST */ -\fBDST_EET\fP /* Eastern European DST */ -\fBDST_CAN\fP /* Canada */ -\fBDST_GB\fP /* Great Britain and Eire */ -\fBDST_RUM\fP /* Romania */ -\fBDST_TUR\fP /* Turkey */ -\fBDST_AUSTALT\fP /* Australian style with shift in 1986 */ -.EE -.in -.PP -Of course it turned out that the period in which -Daylight Saving Time is in force cannot be given -by a simple algorithm, one per country; indeed, -this period is determined by unpredictable political -decisions. -So this method of representing timezones -has been abandoned. -.SH NOTES -The time returned by -.BR gettimeofday () -.I is -affected by discontinuous jumps in the system time -(e.g., if the system administrator manually changes the system time). -If you need a monotonically increasing clock, see -.BR clock_gettime (2). -.PP -Macros for operating on -.I timeval -structures are described in -.BR timeradd (3). -.SH SEE ALSO -.BR date (1), -.BR adjtimex (2), -.BR clock_gettime (2), -.BR time (2), -.BR ctime (3), -.BR ftime (3), -.BR timeradd (3), -.BR capabilities (7), -.BR time (7), -.BR vdso (7), -.BR hwclock (8) |