weird script in crontab

Shell Programming and Scripting
1

Hello here's the first line's of the code
that works perfect on command line
but not as a crontab job ???

crontab:

15 * * * * /root/scripts/checkclamd_mem.sh

script:

#!/bin/bash

# Checks Memory of the Clamav-daemon and it's .pid file
# restarts if over the LIMIT. Starts if pid file not found

LOG="/var/log/scripts/checkclamd_mem.log"

# Limit in Mo
LIMIT=120

PID=$(ps waux | grep "clamd" | grep -v "grep" | awk '{ print $2 }')
MEM=$(ps waux | grep "clamd" | grep -v "grep" | awk '{ print $6 }')

the output of PID and MEM:

Why the all those values when running in crontab ?
awk error ??
If someone can help me !!!???

Nils

2

may be if wiil be helpfull if you write full path to all binary - like /usr/bin/grep and /usr/bin/ps

you can delete 'grep command' - it possiable use only awk:
/usr/bin/ps waux | /usr/bin/awk '/clamd/{ print $2 }'

and may be better in cron use 'nohup' or redirect output like
15 * * * * /root/scripts/checkclamd_mem.sh > /tmp/out.txt 2>&1

3

It might be that there are multiple clam daemons running, or maybe that clamd is actually a username or something. Try this:

PID=$(ps hax -o pid,cmd | awk '/clamd$/ { print $1; exit; }')
MEM=$(ps wuh $PID | awk '{ print $6 }' )

(The MEM line grabs the memory usage as before, but this time only of the actual PID as found in the previous line.)

4

thx, no there are no clamd username and just 1 clamd daemon running.
The "exit;" in awk fixed it:

 PID=$(ps hax -o pid,cmd | awk '/clamd$/ { print $1; exit; }')
# and this also
PID=$(ps waux | grep "clamd" | grep -v "grep" | awk '{ print $2; exit; }')

It now works !! but I still don't understand Why ? the different behaviors
when executed from command line
or executed from crontab