easy unix time change

[Olivier Drouin]

Hi,
My memory is tricking me. I knew a way in solaris to change the date/time of a system in the shell of a user.

The machine time itself is still alright but it can be ahead a day or two for a sub-shell. ( I'm writing a script that delete log files after n-days, thats why I need this ).

It was only a matter of setting an environment variable ( TIMEZONE ? TZ ? ).

Somebody knows ?

[Mark Grant]

The TZ variable is only far adding and subtracting hours from the system clock. You shouldn't really use it for dealing with clock drift!

You shoudld set up "ntp" and synchronize your time with a public "ntp" server.

Oh and remember to synch your hardware clock.

[Martin P.J. Zinser]

The command to change the time on the commandline would be date -s . I do agree that setting up NTP is the much preferrable solution.

Greetings, Martin

[Huc_1]

Best is ntp but as a one of

Man rdate

ex: (just to see other node (time server) date/time

rdate -p 'remote_node'


J-P

[Olivier Drouin]

No guys you dont get my problem. My systems uses NTP and are all in sync.

I just want to "emulate" the time in a user subshell.

[Huc_1]

Sorry if I sound a bit dumm, I probably am !

What do mean by emulate in a sub-shell


J-P ( Is confused now !)

[Olivier Drouin]

Say the daemon on the machines are still on the correct time ( set be NTP ) so the logfiles are not f***** and creation/modification date of files is correct.

Now I login on the machine. ssh user@mybox. Everything that I start in this sessions is "subshell", ie: everyting I run or do is a child/fork of the "bash" instance I created when I log on.

Now I want everything in this session to use a time ( `date` output for example ) different than the real time of the machine that the other users/process/daemon.

I know it sounds silly but it can be done, I already did it but I just dont rememeber how.

BTW, for a dumb you have many karma points ! ;-)

[Olivier Drouin]

I need this because I'm writing a script that deletes logifles after, say, 5 days.

Now I really dont want to 'touch' some files. Wait 5 days to test my system. And wait until next tomorrow if something doesnt work.

I want to:

1 go backward 5 days,
2 'touch' some files.
3 Reset the good time.
4 Test my script.
5 And repeat if I made a mistake.

[Tony Contratto · Accepted solution]

Hi Olivier,

Why not just use touch to create the files with whatever date you want. Check the man page for touch for details, but something like the following should work for you.

touch -amt 200312011300 test.file

That should create a new file named test.file with an access and modified time of 1pm on Dec 1, 2003.

--
Tony

[Olivier Drouin]

good! thanks!