the follwing script is running fine , when run from the ksh shell...it runs properly i.e. waits for a file "test.flag" and sends mail accordingly.


But when I schedule it in the crontab ...it does not run at the specified time (it never runs).
I am using ksh

####shell script starts
count=1
while true; do
if test -f test.flag
then
mailx -s "File Found" s.ba@dsc.com s.ba@hcil.in </man/prd2/bat/tmp/found.txt
exit 0
fi
let count="$count + 1"
#####count=$(( $count + 1 ))
sleep 2
####wait (2)
if [ $count -gt 300 ]
then
mailx -s "File not Found" s.ba@dsc.com s.ba@hcil.in </man/prd2/bat/tmp/not_found.txt
exit 0
fi
done

####shell script ends

###ran crontab -l
20 11 * * * /sa/p/brd/tmp/mailer.sh

##### ran uname -X
System = SunOS
Node = ritba
Release = 5.8
KernelID = Generic_108528-24
Machine = sun4u
BusType = <unknown>
Serial = <unknown>
Users = <unknown>
OEM# = 0
Origin# = 1
NumCPU = 2


Please suggest, (the path of .txt files is correct)

As mentioned by you, 'it does not run at the specified time' means it runs after the apecified time or never runs ?

Check "man crontab" for the exact location of cron's files on your system.
Please state the unix/Linux version - there is much variation.

In general:
Check /usr/adm/cron/log to see if the job ran at all.
Run "fuser /usr/adm/cron/log" and check there is a process using the log (i.e. cron is running).
Check mail for the user of the cron for error messages.
Check /usr/adm/cron/cron.allow and /usr/adm/cron/cron.deny to make sure that the user is allowed to run a cron.

Maybe mailx is not on the path for the cron user?

Path is correct ...