Linux Fundamentals 27

Mission Planning     at    at time    at >     at + d  Submit Task         at Job queue: Use a single letter representation     at -q b ...  b Queue     at -l =  atq  View Jobs     at -d job NUM  Delete a job that has not yet been executed      atrm JOB_NAME    at  Batch Mode         at  -f at_job_file TIME        TIME:  Blur Time  now  , noon , midnight , teatime , tomorrow              mail Command          Interactive mode receive mail          interactive mode send mail          -s  "Subject"         < file              redirect rejection messages by output         &> /dev/null         > /dev/null 2 >&1         MAILTO =  ""            batch   with at is not able to specify the time, it automatically selects the system when idle execution        periodic task scheduling  cron     crond  Daemon          System cron           Files  /etc/cron             User cron        /var/spool/cron/username , /etc/cron          time notation: (user-name command to be excuted)                     Day    month    Week               *   *   *    *   *                         eg: */3 * * * *  Execute every 3 minutes                      Time notation:           1  Each time bit should use values in its available valid range of values            2  on a time bit * Represents all valid values for the corresponding            3 -  represents consecutive point-in-time values (neighboring points) &NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;4&NBSP, representing discrete point-in-time values             5 /#  indicates that every # time is executed once in a specified point in time, eg: 5 - 45/3 * * * * 

Linux Fundamentals 27