我只想保留前 5 个计划作业(如最低的 5 个作业 ID 号)并删除其余的计划 atq 作业。我怎样才能做到这一点?
答案1
在我的 Debian 系统上,at
按计划启动时间而不是按指定顺序对作业进行排序at
:
$ for i in 10 20 30 40 50 60 70; do
at now + "$i" min < scripts/foo.sh; sleep 1;
done
warning: commands will be executed using /bin/sh
job 8 at Sat Apr 18 15:31:00 2015
warning: commands will be executed using /bin/sh
job 9 at Sat Apr 18 15:41:00 2015
warning: commands will be executed using /bin/sh
job 10 at Sat Apr 18 15:51:00 2015
warning: commands will be executed using /bin/sh
job 11 at Sat Apr 18 16:01:00 2015
warning: commands will be executed using /bin/sh
job 12 at Sat Apr 18 16:12:00 2015
warning: commands will be executed using /bin/sh
job 13 at Sat Apr 18 16:22:00 2015
warning: commands will be executed using /bin/sh
job 14 at Sat Apr 18 16:32:00 2015
$ atq
9 Sat Apr 18 15:41:00 2015 a terdon
11 Sat Apr 18 16:01:00 2015 a terdon
10 Sat Apr 18 15:51:00 2015 a terdon
12 Sat Apr 18 16:12:00 2015 a terdon
8 Sat Apr 18 15:31:00 2015 a terdon
14 Sat Apr 18 16:32:00 2015 a terdon
13 Sat Apr 18 16:22:00 2015 a terdon
正如您所看到的,at
将按照作业的运行顺序对作业进行编号,但atq
以明显随机的顺序列出它们。
要删除 列出的前 5 个作业
atq
,您可以执行以下操作:atrm $(atq | head -5 | cut -f 1)
要根据启动顺序删除前 5 个作业,请执行以下操作:
atrm $(atq | sort -n | head -5 | cut -f 1)
答案2
这删除了前5个,所以是错误的,如果你能找出如何做倒立头(删除头),那么你就会有答案。wc
和的组合tail
可以做到这一点。
atq | sort -g | head -5 | cut -f1 | xargs atrm
正确答案
atq | sort -g | tail -n +6 | cut -f1 | xargs atrm