CRON(8) System Manager's Manual CRON(8)NAME
cron - clock daemon
SYNOPSIS
/usr/sbin/cron
DESCRIPTION
Cron executes commands at specified dates and times according to the instructions in the files /etc/crontab and /etc/crontab.local. None,
either one, or both of these files may be present. Since cron never exits, it should only be executed once. This is best done by running
cron from the initialization process through the file /etc/rc; see init(8).
The crontab files consist of lines of seven fields each. The fields are separated by spaces or tabs. The first five are integer patterns
to specify:
o minute (0-59)
o hour (0-23)
o day of the month (1-31)
o month of the year (1-12)
o day of the week (1-7 with 1 = Monday)
Each of these patterns may contain:
o a number in the range above
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 user name: the command will be run with that user's uid and permissions. The seventh field consists of all the text
on a line following the sixth field, including spaces and tabs; this text is treated as a command which is executed by the Shell at the
specified times. A percent character (``%'') in this field is translated to a new-line character.
Both crontab files are checked by cron every minute, on the minute.
FILES
/etc/crontab
/etc/crontab.local
7th Edition October 23, 1996 CRON(8)
Check Out this Related Man Page
CRON(8) System Manager's Manual CRON(8)NAME
cron - daemon to execute scheduled commands (Vixie Cron)
SYNOPSIS
cron
DESCRIPTION
Cron should be started from /etc/rc or /etc/rc.local. It will return immediately, so you don't need to start it with '&'.
Cron searches /var/spool/cron for crontab files which are named after accounts in /etc/passwd; crontabs found are loaded into memory. Cron
also searches for /etc/crontab and the files in the /etc/cron.d/ directory, which are in a different format (see crontab(5)). Cron then
wakes up every minute, examining all stored crontabs, checking each command to see if it should be run in the current minute. When execut-
ing commands, any output is mailed to the owner of the crontab (or to the user named in the MAILTO environment variable in the crontab, if
such exists).
Additionally, cron checks each minute to see if its spool directory's modtime (or the modtime on /etc/crontab) has changed, and if it has,
cron will then examine the modtime on all crontabs and reload those which have changed. Thus cron need not be restarted whenever a crontab
file is modified. Note that the Crontab(1) command updates the modtime of the spool directory whenever it changes a crontab.
SEE ALSO crontab(1), crontab(5)AUTHOR
Paul Vixie <paul@vix.com>
4th Berkeley Distribution 20 December 1993 CRON(8)
Hi,
I trying to include a script in my crontab as user. I used "crontab -e" to include my script there but does not seem to work. If I understand correctly it is set to run at 11:20 every day, correct?
Can anybody identify any error?
<pre>
#Sun Microsystems Inc. SunOS 5.7 Generic... (19 Replies)
Hi friends,
i have written one small script named as "size.sh".....
while running its giving
syntax error at line no 2: 'str=$' unexpected.
How to run this file ??? please help me.
file content is :
-----------------------------
#!/bin/sh
str=$( df -k | grep /usr/local)... (14 Replies)
Hello expert,
What I want is to determine whether the script is called from CRON or it is executed interactively?
I tried the following but no luck:
#!/bin/ksh
cronID=`pgrep -x cron`
GPID=`ps -ef -o ppid,pid | grep " $PPID$" | awk '{print $1}'`
if ; then
echo I am being run... (15 Replies)
Hi all,
I am finding a issue with crontab that whatever the changes I made in the crontab file on the previous day wont be getting replicated today.
I saved the editor properly.
What would be the reason behind this.
For Eg: 03 12 * * * /gdbuat4/backupscripts/dailyexp10g.sh replaced to ... (33 Replies)
Hi All,
Do apologise, for it has been a long while since I was last on the forum. I've been doing documentation and primiarily Windows efforts for some while now. :(
We are running a HP-UX 11.23 unit. This morning two separate crontab users executed shutdown scripts of their respective... (14 Replies)
Hi Friends,
I'm working on a perl script, which seems to be simpler. But I'm very new to PERL scripting.
I have a comma separated data file, from which I need to extract only the seventh field data out of available twenty fields to an array using perl.
Any help would be much appreciated.
... (17 Replies)
Hi,
I am programming a Western Digital ShareSpace network disk system.
I installed a cron from ipkg. (explained here: mybookworld.wikidot.com/sharespace ShareSpace - Hacking WD MyBook World Ed)
Cron runs:
/etc $ ps -fe | grep cron
6082 root 616 S < /opt/sbin/cron
18635 root ... (15 Replies)
Hi,
I need to schedule a script in crontab which should run at 01:00 am in the morning and should run for every 15 days in a month.
How to schedule this by using crontab?
Many thanks.
Rgds, (13 Replies)
Hi
I have this posted in the Solaris section also so apologies if not permitted to post here also.
problem is that my cron will not run a script that runs perfectly fine from command line. The script is written in sh but contains reference to a .pl.
Initial script only had path... (14 Replies)
Hi
I have successfukky created a sh script that runs perfectly well when run. It contains within a pl script that when run through a crontab will not run. Are there restrictions running a pl in cron? (14 Replies)
Hi,
I have a script which checks to see if an app is running and will restart it if it is not.
For some reason when I run it from the crontab it always says it is not running.
The script is as follows: -
#!/bin/sh
#
# The following script will look for the PID of SickBeard and output... (15 Replies)
hi,
i have to backup a database everyday on a Sun Microsystem.
i have been looking around and have found that crontab might be the answer.
the list of steps that have to be followed for me to get the database is:
1. on cmd telnet the equipment.
2. put the user name and password.
3. i... (20 Replies)
I can run manually script of ntopdump.sh but crontab can't run this script very five minutes.
# crontab -l
*/3 * * * * root sh /root/ping.sh
*/5 * * * * root sh /root/ntopdump.sh
#
# pwd
/root
# ls -l
total 88
-rwxrwxr-x 1 root root 1645 Jun 14 19:01 anaconda-ks.cfg
drwxrwxr-x 2 root... (14 Replies)
dear master,
I have a question about crontab,
I trying create a file.
#touch myfile
#vi myfile
errpt >> reporterror /mydirectory
that content myfile.
and I try, insert at crontab -e
45 14 * * * /myderectory/myfile >> /mydirectory
... (13 Replies)
Hello
I have a problem with the crontab command
when I run a code containing Curl on the command line it runs without fail but as soon as I program it with crontab it executes everything except the curl returns fail
thank you for helping me to resolve this problem because since Monday I look... (14 Replies)