Answer / swapna

cron command is used to schedule the task daily at the same
time repeatedly.

"at" command is used to schedule the task only once i.e to
run only one time.

Answer / sureshreddy

at: this command to schedule the specified job onl once.
cron: this command to schedule the specified job repeatedly.

Answer / vishnu

Cron can be scheduled with different choices
(minute,hour,month,dayofmonth,dayofweek). cron can be
edited,deleted,listed,scheduled at any time and for
repeated time intervals.
AT can be scheduled for once.cannot be edited, can be
deleted, can be listed.

so, 2 main differences:-
cron:can be scheduled for repeated jobs
AT: can be scheduled for only once

cron can be edited
AT cannot be edited, after its schedule.

both can facilitate listing and deletion

Answer / jagadeeb choudhury

Cron: is a daemond process its run periodical.Mince you can
run it in every (sec,min,hour,day,date,Month).We can't
remove a cron job we commenting that only.
here 6 fild to schedule a cron job.

At: only run on particular time specifies by user who
schedule that time you can remove a at job.

Ex:-
$at 9:30
>a.txt
>b.txt
[ctl+d]



Thanks,
Jagadeeb@gmail.com

Answer / test

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