Bug#619082: dash: implement variable $RANDOM
(resending because I can't spell. :/ Sorry for the noise.)
Hi Pedro,
Pedro Zorzenon Neto wrote:
After upgrading to squeeze and answering yes to install question of
using dash as default shell for non-interactive users, all my cronjobs
that use $RANDOM variable to delay some random seconds of running time
stopped working.
I don't think this functionality belongs in dash. For example, I
find that the sleep command in
Example of a simple cronjob which runs with a random delay of
0 ~ 327 seconds (to prevent network peaks of all the machines):
*/30 * * * * sleep $(($RANDOM/100)) do_something_network_related
is better written (more portably and more intuitively) as
sleep $(awk 'BEGIN {srand(); printf %d\n, rand()*327}')
or
awk 'BEGIN { srand(); system(sleep int(rand() * 327)) }'
even though this is a little longer.
On the other hand, I would definitely like a way for users to be able
to easily choose a different shell to be used by cron, so they would
be less at the mercy of the cruel sysadmin. What do you think?
Thanks for writing,
Jonathan
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Bug#619082: dash: implement variable $RANDOM
I don't think this functionality belongs in dash. For example, I
find that the sleep command in
Example of a simple cronjob which runs with a random delay of
0 ~ 327 seconds (to prevent network peaks of all the machines):
*/30 * * * * sleep $(($RANDOM/100)) do_something_network_related
is better written (more portably and more intuitively) as
sleep $(awk 'BEGIN {srand(); printf %d\n, rand()*327}')
or
awk 'BEGIN { srand(); system(sleep int(rand() * 327)) }'
even though this is a little longer.
nice idea...
*/30 * * * * perl -e sleep rand(327); do_something_network_related
for the ones that like perl :-)
I think that is dash is supposed to replace bash, it should implement
$RANDOM... but this is only my personal opinion :-)
On the other hand, I would definitely like a way for users to be able
to easily choose a different shell to be used by cron, so they would
be less at the mercy of the cruel sysadmin. What do you think?
If you put:
SHELL=/bin/something
at the begining of your crontab, all the lines will be run with your
prefered shell.
Thanks,
Pedro
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Bug#619082: dash: implement variable $RANDOM
clone 619082 -1 retitle -1 dash: package description does not explain goals well severity -1 minor submitter -1 ! quit Pedro Zorzenon Neto wrote: [out of order for convenience] If you put: SHELL=/bin/something at the begining of your crontab, all the lines will be run with your prefered shell. Ah, that's excellent! I should have checked crontab(5). I think that is dash is supposed to replace bash, it should implement $RANDOM... but this is only my personal opinion :-) Ah, interesting --- dash is not intended to replace bash but now that I check I see the current package description suggests it might be. By contrast, Herbert's webpage says: DASH is a POSIX-compliant implementation of /bin/sh that aims to be as small as possible. It does this without sacrificing speed where possible. In fact, it is significantly faster than bash (the GNU Bourne-Again SHell) for most tasks. From this we see that dash is meant to to be * POSIX-compliant * small * reasonably fast Meanwhile bash is more powerful and definitely has its place (especially for features like programmatic completion imho). The package could use some help from a wordsmith to convey: - for a full-featured, bash-compatible shell, see the bash package. :) - for a POSIX compliance checker, see the posh package. Thanks for a useful reminder. -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Bug#619082: dash: implement variable $RANDOM
Package: dash Version: 0.5.5.1-7.4 Severity: wishlist Hi, After upgrading to squeeze and answering yes to install question of using dash as default shell for non-interactive users, all my cronjobs that use $RANDOM variable to delay some random seconds of running time stopped working. Please implement this in dash. Example of a simple cronjob which runs with a random delay of 0 ~ 327 seconds (to prevent network peaks of all the machines): */30 * * * * sleep $(($RANDOM/100)) do_something_network_related Thanks, Pedro -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
