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linux下crontab中%的使用
crontab中下面的腳本不能
0 1 * * * (cd /u01/prod; rsync -avz app 192.168.0.192:/u01/prod/) &>/home/applprod/backuplog/rsync_`date +%Y%m%d_%H%M%S`.log
執(zhí)行的時(shí)候，/var/log/messages日志中顯示：
Sep 22 22:50:01 ebsapp CROND[13389]: (applprod) CMD ((cd /u01/prod; rsync -avz app 192.168.0.192:/u01/prod/) &>/home/applprod/backuplog/rsync_`date +)
好像是命令被截?cái)嗟臉幼印?/p>
于是我把要執(zhí)行的命令都封裝到一個(gè)腳本中，放到crontab中執(zhí)行。
但是稍后查看crontab的manpage時(shí)發(fā)現(xiàn)，%在crontab中有特殊含義：
The "sixth" field (the rest of the line) specifies the command to be run. The entire command portion of the line, up to a new- line or % character, will be executed by /bin/sh or by the shell specified in the SHELL variable of the cronfile. Percent-signs (%) in the command, unless escaped with backslash (), will be changed into newline characters, and all data after the first % will be sent to the command as standard input.
到這里問題已經(jīng)清楚了，并不是crontab命令被截?cái)啵潜焕斫獬闪硗獾暮x了，解決的方法也有了，就是將%進(jìn)行轉(zhuǎn)義，修改之后的腳本變成了：
03 23 * * * (cd /u01/prod; rsync -avz app 192.168.0.192:/u01/prod/) &>/home/applprod/backuplog/rsync_`date +%Y%m%d_%H%M%S`.log
