Convert a calendar time to a string
String_Type ctime(Long_Type secs)
This function returns a string representation of the time as given
by secs seconds since 00:00:00 UTC, Jan 1, 1970.
Break down a time in seconds to the GMT timezone
Struct_Type gmtime (Long_Type secs)
The gmtime function is exactly like localtime except
that the values in the structure it returns are with respect to GMT
instead of the local timezone. See the documentation for
localtime for more information.
On systems that do not support the gmtime C library function,
this function is the same as localtime.
Break down a time in seconds to the local timezone
Struct_Type localtime (Long_Type secs)
The localtime function takes a parameter secs
representing the number of seconds since 00:00:00, January 1 1970
UTC and returns a structure containing information about secs
in the local timezone. The structure contains the following
Int_Type fields:
tm_sec The number of seconds after the minute, normally
in the range 0 to 59, but can be up to 61 to allow for
leap seconds.
tm_min The number of minutes after the hour, in the
range 0 to 59.
tm_hour The number of hours past midnight, in the range
0 to 23.
tm_mday The day of the month, in the range 1 to 31.
tm_mon The number of months since January, in the range
0 to 11.
tm_year The number of years since 1900.
tm_wday The number of days since Sunday, in the range 0
to 6.
tm_yday The number of days since January 1, in the
range 0 to 365.
tm_isdst A flag that indicates whether daylight saving
time is in effect at the time described. The value is
positive if daylight saving time is in effect, zero if it
is not, and negative if the information is not available.
Convert a time-structure to seconds
secs = mktime (Struct_Type tm)
The mktime function is essentially the inverse of the
localtime function. See the documentation for that function
for more details.
Format a date and time string
str = strftime (String_Type format [,Struct_Type tm])
The strftime creates a date and time string according to a
specified format. If called with a single argument, the current
local time will be used as the reference time. If called with two
arguments, the second argument specifies the reference time, and
must be a structure with the same fields as the structure returned
by the localtime function.
The format string may be composed of one or more of the following format descriptors:
%A full weekday name (Monday)
%a abbreviated weekday name (Mon)
%B full month name (January)
%b abbreviated month name (Jan)
%c standard date and time representation
%d day-of-month (01-31)
%H hour (24 hour clock) (00-23)
%I hour (12 hour clock) (01-12)
%j day-of-year (001-366)
%M minute (00-59)
%m month (01-12)
%p local equivalent of AM or PM
%S second (00-59)
%U week-of-year, first day Sunday (00-53)
%W week-of-year, first day Monday (00-53)
%w weekday (0-6, Sunday is 0)
%X standard time representation
%x standard date representation
%Y year with century
%y year without century (00-99)
%Z timezone name
%% percent sign
message (strftime ("Today is %A, day %j of the year"));
tm = localtime (0);
message (strftime ("Unix time 0 was on a %A", tm));
Reset the CPU timer
_tic ()
The _tic function resets the internal CPU timer. The
_toc may be used to read this timer. See the documentation
for the _toc function for more information.
Reset the interval timer
void tic ()
The tic function resets the internal interval timer. The
toc may be used to read the interval timer.
The tic/toc functions may be used to measure execution times. For example, at the slsh prompt, they may be used to measure the speed of a loop:
slsh> tic; loop (500000); toc;
0.06558
On Unix, this timer makes use of the C library gettimeofday
function.
Get the current calendar time in seconds
Long_Type _time ()
The _time function returns the number of elapsed seconds since
00:00:00 UTC, January 1, 1970. A number of functions (ctime,
gmtime, localtime, etc.) are able to convert such a
value to other representations.
Return the current date and time as a string
String_Type time ()
This function returns the current time as a string of the form:
Sun Apr 21 13:34:17 1996
Convert a time structure for the GMT timezone to seconds
Long_Type secs = timegm(Struct_Type tm)
timegm is the inverse of the gmtime function.
Get process times
Struct_Type times ()
The times function returns a structure containing the
following fields:
tms_utime (user time)
tms_stime (system time)
tms_cutime (user time of child processes)
tms_cstime (system time of child processes)
Not all systems support this function.
Get the elapsed CPU time for the current process
Double_Type _toc ()
The _toc function returns the elapsed CPU time in seconds since
the last call to _tic. The CPU time is the amount of time the
CPU spent running the code of the current process.
This function may not be available on all systems.
The implementation of this function is based upon the times
system call. The precision of the clock is system dependent and may
not be very accurate for small time intervals. For this reason, the
tic/toc functions may be more useful for small time-intervals.
Read the interval timer
Double_Type toc ()
The toc function returns the elapsed time in seconds since
the last call to tic. See the documentation for the
tic function for more information.