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crontab(5) [ultrix man page]

crontab(5)							File Formats Manual							crontab(5)

       crontab - clock daemon table file


       The  command  executes  at  specified dates and times according to the instructions in the file. The file consists of lines with six fields
       each.  The format for a line is as follows:

	      minute hour day month weekday command

       The following list defines each field in the line:

       minute (0-59)  The exact minute that the command sequence executes.

       hour (0-23)    The hour of the day that the command sequence executes.

       day (1-31)     The day of the month that the command sequence executes.

       month (1-12)   The month of the year that the command sequence executes.

       weekday (1-7)  The day of the week that the command sequence executes. Monday = 1, Tuesday = 2, and so forth.

       command	      The complete command sequence variable that is to be executed.  Note that the command string must conform  to  Bourne  shell

       The first five integer fields may be specified as follows:

       o   A single number in the specified range

       o   Two numbers separated by a minus, meaning a range inclusive

       o   A list of numbers separated by commas, meaning any of the numbers

       o   An asterisk meaning all legal values

       The sixth field is a string that is executed by the shell at the specified times.  A percent sign (%) in this field is translated to a new-
       line character.	Only the first line of the command field, up to a percent sign (%) or end of line, is executed by the  shell.	The  other
       lines are made available to the command as standard input.

       The following example is part of a file:
       # periodic things
       0,15,30,45 * * * * (echo '^M' `date`; echo '') >/dev/console
       0,15,30,45 * * * * /usr/lib/atrun

       # daily stuff
       5 4 * * * sh /usr/adm/newsyslog
       15 4 * * * ( cd /usr/preserve; find . -mtime +7 -a -exec rm -f {} ; )
       20 4 * * * find /usr/msgs -mtime +21 -a ! -perm 444 -a ! -name bounds
	    -a -exec rm -f {} ;

       # NOTE: The above line is wrapped.

       # local cleanups
       30 4 * * * find /usr/spool/mqueue -type f -mtime +5 -name df-exec rm {} ;
       35 4 * * * find /usr/spool/mqueue -type f -mtime +5 -name tf-exec rm {} ;
       40 4 * * * find /usr/spool/rwho -type f -mtime +21 -exec rm {} ;

       # redirecting error output
       0 17 * * 1,3,5 /bin/tar -cv /usr/sysads/smith > /dev/console 2>&1

See Also
       sh(1), cron(8)
       Guide to System Environment Setup


Check Out this Related Man Page

AT(1)							      General Commands Manual							     AT(1)

at - execute commands at a later time SYNOPSIS
at time [ day ] [ file ] DESCRIPTION
At squirrels away a copy of the named file (standard input default) to be used as input to sh(1) at a specified later time. A cd(1) com- mand to the current directory is inserted at the beginning, followed by assignments to all environment variables. When the script is run, it uses the user and group ID of the creator of the copy file. The time is 1 to 4 digits, with an optional following `A', `P', `N' or `M' for AM, PM, noon or midnight. One and two digit numbers are taken to be hours, three and four digits to be hours and minutes. If no letters follow the digits, a 24 hour clock time is understood. The optional day is either (1) a month name followed by a day number, or (2) a day of the week; if the word `week' follows invocation is moved seven days further off. Names of months and days may be recognizably truncated. Examples of legitimate commands are at 8am jan 24 at 1530 fr week At programs are executed by periodic execution of the command /usr/lib/atrun from cron(8). The granularity of at depends upon how often atrun is executed. Standard output or error output is lost unless redirected. FILES
/usr/spool/at/yy.ddd.hhhh.uu activity to be performed at hour hhhh of year day ddd of year yy. uu is a unique number. /usr/spool/at/lasttimedone contains hhhh for last hour of activity. /usr/spool/at/past directory of activities now in progress /usr/lib/atrun program that executes activities that are due pwd(1) SEE ALSO
calendar(1), cron(8) DIAGNOSTICS
Complains about various syntax errors and times out of range. BUGS
Due to the granularity of the execution of /usr/lib/atrun, there may be bugs in scheduling things almost exactly 24 hours into the future. AT(1)

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