xnu-3248.20.55.tar.gz

[apple/xnu.git] / bsd / man / man2 / gettimeofday.2

diff --git a/bsd/man/man2/gettimeofday.2 b/bsd/man/man2/gettimeofday.2
index febc61dcdba4275af1d94dc15ea2fb5dcd18d74c..179e9bc0cb44e5d620552fee9cc3ae529f0c7360 100644 (file)
--- a/bsd/man/man2/gettimeofday.2
+++ b/bsd/man/man2/gettimeofday.2
@@ -33,7 +33,7 @@
 .\"
 .\"     @(#)gettimeofday.2     8.2 (Berkeley) 5/26/95
 .\"
-.Dd May 26, 1995
+.Dd August 5, 2008
 .Dt GETTIMEOFDAY 2
 .Os BSD 4
 .Sh NAME
@@ -43,14 +43,16 @@
 .Sh SYNOPSIS
 .Fd #include <sys/time.h>
 .Ft int
-.Fn gettimeofday "struct timeval *tp" "struct timezone *tzp"
+.Fo gettimeofday
+.Fa "struct timeval *restrict tp"
+.Fa "void *restrict tzp"
+.Fc
 .Ft int
-.Fn settimeofday "const struct timeval *tp" "const struct timezone *tzp"
+.Fo settimeofday
+.Fa "const struct timeval *tp"
+.Fa "const struct timezone *tzp"
+.Fc
 .Sh DESCRIPTION
-.Bf -symbolic
-Note: timezone is no longer used; this information is kept outside
-the kernel.
-.Ef
 .Pp
 The system's notion of the current Greenwich time and the current time
 zone is obtained with the
@@ -62,10 +64,24 @@ since midnight (0 hour), January 1, 1970.  The resolution of the system
 clock is hardware dependent, and the time may be updated continuously or
 in ``ticks.''  If
 .Fa tp
-or
+is NULL
+and
+.Fa tzp
+is non-NULL,
+.Fn gettimeofday
+will populate the timezone struct in 
+.Fa tzp .
+If 
+.Fa tp
+is non-NULL and
+.Fa tzp 
+is NULL, then only the timeval struct in
+.Fa tp
+is populated. If both
+.Fa tp
+and
 .Fa tzp
-is NULL, the associated time
-information will not be returned or set.
+are NULL, nothing is returned.
 .Pp
 The structures pointed to by
 .Fa tp
@@ -76,18 +92,28 @@ are defined in
 as:
 .Pp
 .Bd -literal
+
 struct timeval {
-       long    tv_sec;         /* seconds since Jan. 1, 1970 */
-       long    tv_usec;        /* and microseconds */
+       time_t       tv_sec;   /* seconds since Jan. 1, 1970 */
+       suseconds_t  tv_usec;  /* and microseconds */
 };
 
 struct timezone {
        int     tz_minuteswest; /* of Greenwich */
        int     tz_dsttime;     /* type of dst correction to apply */
 };
+
 .Ed
 .Pp
 The 
+.Fa timeval
+structure specifies a time value in seconds and microseconds.
+The values in
+.Fa timeval
+are opaque types whose length may vary on different machines;
+depending on them to have any given length may lead to errors.
+.Pp
+The 
 .Fa timezone
 structure indicates the local time zone
 (measured in minutes of time westward from Greenwich),
@@ -97,7 +123,7 @@ the appropriate part of the year.
 .Pp
 Only the super-user may set the time of day or time zone.
 If the system securelevel is greater than 1 (see
-.Xr init 8 ),
+.Xr launchd 8 ),
 the time may only be advanced.
 This limitation is imposed to prevent a malicious super-user
 from setting arbitrary time stamps on files.
@@ -118,10 +144,24 @@ An argument address referenced invalid memory.
 .It Bq Er EPERM
 A user other than the super-user attempted to set the time.
 .El
+.Sh LEGACY SYNOPSIS
+.Fd #include <sys/time.h>
+.Pp
+.Ft int
+.br
+.Fo gettimeofday
+.Fa "struct timeval *tp"
+.Fa "struct timezone *tzp"
+.Fc ;
+.Pp
+The type of
+.Fa tzp
+has changed.
 .Sh SEE ALSO
 .Xr date 1 ,
 .Xr adjtime 2 ,
 .Xr ctime 3 ,
+.Xr compat 5 ,
 .Xr timed 8
 .Sh HISTORY
 The