我的crontab看起來像：

root@slack13x64:~# crontab -l -u dnd

# some variables

SHELL=/bin/bash

PATH=/bin:/usr/bin:/usr/local/bin:/home/dnd/bin

MAILTO=root

# Actual jobs

40 20 * * * /home/dnd/cron_jobs/some_job.sh

55 23 * * Fri /home/dnd/cron_jobs/other_job.py

作業運行幾乎沒問題,因為crontab無法設置所有變量：

Sep 1 20:40:01 slack13x64 crond[2325]: Failed parsing crontab for user dnd: SHELL=/bin/bash

Sep 1 20:40:01 slack13x64 crond[2325]: Failed parsing crontab for user dnd: PATH=/bin:/usr/bin:/usr/local/bin:/home/dnd/bin

Sep 1 20:40:01 slack13x64 crond[2325]: Failed parsing crontab for user dnd: MAILTO=root

操作系統：slackware 13 x64,crontab 4.4

問題是我錯過了什么？是否支持從crontab中刪除初始環境變量或運行此作業的用戶應該分配給某個組？