man3/ftime.3

   1 .\" Hey Emacs! This file is -*- nroff -*- source.
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   3 .\" Copyright (c) 1993 Michael Haardt
   4 .\" (michael@moria.de)
   5 .\" Fri Apr  2 11:32:09 MET DST 1993
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  27 .\" Modified Sat Jul 24 14:23:14 1993 by Rik Faith (faith@cs.unc.edu)
  28 .\" Modified Sun Oct 18 17:31:43 1998 by Andries Brouwer (aeb@cwi.nl)
  29 .\" 2008-06-23, mtk, minor rewrites, added some details
  30 .\"
  31 .TH FTIME 3 2009-03-15 "GNU" "Linux Programmer's Manual"
  32 .SH NAME
  33 ftime \- return date and time
  34 .SH SYNOPSIS
  35 .B "#include <sys/timeb.h>"
  36 .sp
  37 .BI "int ftime(struct timeb *" tp );
  38 .SH DESCRIPTION
  39 This function returns the current time, in seconds and milliseconds
  40 since the Epoch (00:00:00 UTC, 1 January 1970).
  41 The time is returned in
  42 .IR tp ,
  43 which is declared as follows:
  44 .sp
  45 .in +4n
  46 .nf
  47 struct timeb {
  48     time_t         time;
  49     unsigned short millitm;
  50     short          timezone;
  51     short          dstflag;
  52 };
  53 .fi
  54 .in
  55 .LP
  56 Here \fItime\fP is the number of seconds since the Epoch,
  57 and \fImillitm\fP is the number of milliseconds since \fItime\fP
  58 seconds since the Epoch.
  59 The \fItimezone\fP field is the local timezone measured in minutes
  60 of time west of Greenwich (with a negative value indicating minutes
  61 east of Greenwich).
  62 The \fIdstflag\fP field
  63 is a flag that, if nonzero, indicates that Daylight Saving time
  64 applies locally during the appropriate part of the year.
  65 .LP
  66 POSIX.1-2001 says that the contents of the \fItimezone\fP and \fIdstflag\fP
  67 fields are unspecified; avoid relying on them.
  68 .SH "RETURN VALUE"
  69 This function always returns 0.
  70 (POSIX.1-2001 specifies, and some systems document, a \-1 error return.)
  71 .SH "CONFORMING TO"
  72 4.2BSD, POSIX.1-2001.
  73 POSIX.1-2008 removes the specification of
  74 .BR ftime ().
  75
  76 This function is obsolete.
  77 Don't use it.
  78 If the time in seconds
  79 suffices,
  80 .BR time (2)
  81 can be used;
  82 .BR gettimeofday (2)
  83 gives microseconds;
  84 .BR clock_gettime (2)
  85 gives nanoseconds but is not as widely available.
  86 .SH BUGS
  87 .LP
  88 Under libc4 and libc5 the \fImillitm\fP field is meaningful.
  89 But early glibc2 is buggy and returns 0 there;
  90 glibc 2.1.1 is correct again.
  91 .\" .SH HISTORY
  92 .\" The
  93 .\" .BR ftime ()
  94 .\" function appeared in 4.2BSD.
  95 .SH "SEE ALSO"
  96 .BR gettimeofday (2),
  97 .BR time (2)