Re: Help w/ At Utility

LinuxNovice wrote:

I expected it to display on my screen.

Explain that expectation in terms of this [last quoted] part of the at(1) man page:

$ man at
NAME
at, batch, atq, atrm - queue, examine or delete jobs for
later execution
....
DESCRIPTION
at and batch read commands from standard input or a speci­
fied file which are to be executed at a later time, using
/bin/sh.
....
For example, to run a job at 4pm three days from now, you
would do at 4pm + 3 days, to run a job at 10:00am on July
31, you would do at 10am Jul 31 and to run a job at 1am
tomorrow, you would do at 1am tomorrow.
....

At 4pm three days from now can you *GUARANTEE* that your terminal would still be logged in to accept the output of the command(s) you are submitting to at(1) to run at a later time? If you were today (26 February) to schedule an 'ls' command to run at 10:00am on July 31 could you GUARANTEE that your terminal would still be logged in 155 days later (to accept the output)?

So why should you expect the output of your ls command to appear in your [current] terminal session?

Where do you think the output might go?

Consider: you said your reboot command worked under at(1), but where *EXACTLY* did the output of that command go?

When you run that from a console (in particularly tty1), you'll probably see it shutting down various services, before the reboot and then various services being restarted.

If you were running under X when you submitted the job, I very much doubt that [all] the output appeared in your X terminal[1] (for one, it would have been killed by the reboot - both the terminal /and/ the X server: at which point you'd probably have got a view of tty1)[2]. Your opinion that it worked whereas your ls one didn't was because you saw the effect of the reboot - namely the machine shutting down and restarting - but you saw no effect of the ls command.

[1] Having never tried it, I can't fully comment, and I have no intention of trying it, either.

[2] I would suspect, but again, not having tried it under at(1), can't be anywhere near 100%, that most of the messages of the shutdown phase of the reboot may not have appeared.

Perhaps you'd like to read the at(1) man page and tell me where the output of the command(s) so run goes? (Hint: it occurs near the last bit I quoted above.)

.

Relevant Pages

  • Re: Whatever happened to at, batch, etc?
    ... > throwing a command at the system for one-shot execution while ... at, batch, and their support components. ... rz DOT uni-karlsruhe DOT de ...
    (comp.os.linux.misc)
  • Re: EWF/DUA help needed
    ... > Your script does not reboot the device because it likely fails on the EXECUTE command. ... I have changed the script file, ... it may not be good implementation of your script for the purpose of changing running app with EWF on. ... > With EWF command you just commit a registry change to move/replace the JP.exe file on next reboot. ...
    (microsoft.public.windowsxp.embedded)
  • Re: More efficient way to insert a dataset in .NET 2.0?
    ... individual inserts is killing the execution time of my batch at present. ... >> forever the previous command have influence on the next. ...
    (microsoft.public.dotnet.framework.adonet)
  • RE: Configuring NIC Card
    ... reboot use the full path command and stick it in your /etc/rc.local file. ... If the reader of the message is not the intended recipient, ... We recently upgraded our network switch to a 10/100 Mbps switch. ...
    (RedHat)
  • Re: EWF/DUA help needed
    ... Your script does not reboot the device because it likely fails on the EXECUTE command. ... it may not be good implementation of your script for the purpose of changing running app with EWF on. ... With EWF command you just commit a registry change to move/replace the JP.exe file on next reboot. ...
    (microsoft.public.windowsxp.embedded)