Crontab notes

Current crontab on build machine

[mccreedy@cake]~% crontab -l
# crontab for mccreedy on cake.cit.nih.gov

# mail output to me:
MAILTO=mccreedy@mail.nih.gov
# use zsh no matter what
SHELL=/bin/zsh

#JAVA_HOME=/home/mccreedy/lib/j2sdk1.4.2_08
#JAVACMD=/home/mccreedy/lib/j2sdk1.4.2_08/bin/java
#JAVA_HOME=/home/mccreedy/lib/jdk1.5.0_06

JAVA_HOME=/home/mccreedy/lib/jdk1.6.0_02
#JAVACMD=/home/mccreedy/lib/jdk1.6.0_02/bin/java

ANT_HOME=/home/mccreedy/bin/apache-ant-1.7.0

#PATH=$JAVA_HOME/bin:$ANT_HOME/bin:$PATH

# script directory vars
SCRIPTDIR=/home/mccreedy/bin/scripts
PROJECTDIR=/home/mccreedy/projects

00 23 * * *     $SCRIPTDIR/build/complete-build.zsh -nightly

01 00 * * *     $SCRIPTDIR/build/java_1.5_build.zsh

Crontab notes

• $MAILTO indicates the address that job output should be emailed to.
• $SHELL ensures a consistent (zsh) environment for jobs.
• $JAVA_HOME specifies the default java jdk to use when doing the nightly build (can be overridden by called scripts).
• $ANT_HOME forces a version of ant which is compatible with java 1.6 (default on bern isn't compatible).
• $SCRIPTDIR and $PROJECTDIR are machine and user specific.
• Use 'crontab -l' to print your current crontab. Use 'crontab -e' to make changes using your $EDITOR.

Explanation of crontab job lines

* * * * * <job_command_line>
| | | | |
| | | | +- day of the week (1-7, where 1 => monday)
| | | |
| | | +--- month (1-12)
| | |
| | +----- day of month (1-31)
| |
| +------- hour (0-23)
|
+--------- minute (0-59)

• An asterisk (*) is used to match any time value for a given scheduling field.
• Sends email to $MAILTO if the command prints to stdout or stderr.
• To avoid an email for a command and disregard any output append the following to the command line (zsh/bash):

> /dev/null 2>&1