Re: Getting GMT time

Kevin Kenny wrote: 
Stefaan wrote:

I use following algoritm to determine the GMT time to calculate planet positions 

[snip]

## Following command will convert the local time t to GMT time

clock scan [clock format $t -format "%Y-%m-%d %H:%M:%S" -gmt 1]
1136022869



That is just plain wrong.

Whatever you might believe, [clock seconds] returns the number of
nominal seconds since 00:00 UTC, 1 January 1970.  There is no such
thing as "local seconds" in Tcl.  All time zone conversion happens
inside [clock scan] and [clock format].  If [clock seconds] reports
time in the local time zone and not UTC, that is a bug.  (Nobody
has reported such a bug - and since I'm the mainainer of [clock],
I'd surely know if anyone had.)


--
73 de ke9tv/2, Kevin

OK, I shouldn't have set the starting value with [clock seconds]. But if the starting value represents a local time, not obtained from TCL build-in commands, then in my opinion the algoritm works.
.

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