xref: /openbsd/lib/libc/gen/time.3 (revision 610f49f8)
1.\"	$OpenBSD: time.3,v 1.9 2002/01/24 21:15:20 mickey Exp $
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38.Dd June 4, 1993
39.Dt TIME 3
40.Os
41.Sh NAME
42.Nm time
43.Nd get time of day
44.Sh SYNOPSIS
45.Fd #include <time.h>
46.Ft time_t
47.Fn time "time_t *tloc"
48.Sh DESCRIPTION
49The
50.Fn time
51function returns the value of time in seconds since 0 hours, 0 minutes,
520 seconds, January 1, 1970, Coordinated Universal Time (UTC).
53.Pp
54A copy of the time value may be saved to the area indicated by the
55pointer
56.Fa tloc .
57If
58.Fa tloc
59is a null pointer, no value is stored.
60.Pp
61Upon successful completion,
62.Fn time
63returns the value of time.
64Otherwise a value of
65.Po Fa time_t Pc Ns -1
66is returned and the global variable
67.Va errno
68is set to indicate the error.
69.Sh ERRORS
70The following error codes may be set in
71.Va errno :
72.Bl -tag -width Er
73.It Bq Er EFAULT
74An argument address referenced invalid memory.
75.El
76.Sh SEE ALSO
77.Xr gettimeofday 2 ,
78.Xr ctime 3
79.Sh HISTORY
80A
81.Fn time
82function appeared in
83.At v2
84and used to return time in sixtieths of a second in 32 bits,
85which was to guarantee a crisis every 2.26 years.
86Since the
87.At v6
88.Fn time
89scale was changed to seconds extending the pre-crisis stagnation
90period up to a total of 68 years.
91