I have two different shell script say like
a.sh
b.sh
**code of a.sh**
#!/system/bin/sh
#some code
./xyz/b.sh &
Here we can see i am running b.sh through a.sh file which is postboot script. Each time when device gets reboot it is adding ./xyz/b.sh & which i am trying to avoid.
what i am trying to do :
i need to write a code in such a way that will find if ./system/xyz/b.sh & is already there then no need to add again.
Code :
if pgrep /xyz/b.sh > /dev/null 2>&1
then
echo aplog is running
exit 1
fi
these code is not running. Do not know where i am doing mistake.
Just try:
pgrep b.sh > /dev/null 2>&1
if [ 0 == $? ]
then
...
fi
pgrep will only work on process name, not full path to process name.
Try pgrep -f b.sh or pgrep -x b.sh instead of pgrep -x /xyz/b.sh
Hi test your file existence before creating it with:
filename="/fullpath/xyz/b.sh"
if [ -f "$filename" ]
then
echo "$filename found"
else
echo "$filename not found."
fi
Related
Does monitblocks until file exists in the specified path? I have a shell script which checks for file existence in a while loop and then execute a binary. How can I use monit to avoid the while loop?
#!/bin/sh
while [ ! -f /root/initt ]
do
sleep 1
echo "waiting for /root/initt"
done
echo "initt done"
/usr/bin/myprocess &
check file initt with path /root/initt
if exist then exec "nohup /usr/bin/myprocess </dev/null >/dev/null &"
I have a shell script that does a backup. I set this script in a cron but the problem is that the backup is heavy so it is possible to execute a second rsync before the first ends up.
I thought to launch rsync in a script and then get PID and write a file that script checks if the process exist or not (if this file exist or not).
If I put rsync in background I get the PID but I don't know how to know when rsync ends up but, if I set rsync (no background) I can't get PID before the process finish so I can't write a file whit PID.
I don't know what is the best way to "have rsync control" and know when it finish.
My script
#!/bin/bash
pidfile="/home/${USER}/.rsync_repository"
if [ -f $pidfile ];
then
echo "PID file exists " $(date +"%Y-%m-%d %H:%M:%S")
else
rsync -zrt --delete-before /repository/ /mnt/backup/repositorio/ < /dev/null &
echo $$ > $pidfile
# If I uncomment this 'rm' and rsync is running in background, the file is deleted so I can't "control" when rsync finish
# rm $pidfile
fi
Can anybody help me?!
Thanks in advance !! :)
# check to make sure script isn't still running
# if it's still running then exit this script
sScriptName="$(basename $0)"
if [ $(pidof -x ${sScriptName}| wc -w) -gt 2 ]; then
exit
fi
pidof finds the pid of a process
-x tells it to look for scripts too
${sScriptName} is just the name of the script...you can hardcode this
wc -w returns the word count by words
-gt 2 no more than one instance running (instance plus 1 for the pidof check)
if more than one instance running then exit script
Let me know if this works for you.
Test both for presence of pid file and status of the running process like this:
#!/bin/bash
pidfile="/home/${USER}/.rsync_repository"
is_running =0
if [ -f $pidfile ];
then
echo "PID file exists " $(date +"%Y-%m-%d %H:%M:%S")
previous_pid=`cat $pidfile`
is_running=`ps -ef | grep $previous_pid | wc -l`
fi
if [ $is_running -gt 0 ];
then
echo "Previous process didn't quit yet"
else
rsync -zrt --delete-before /repository/ /mnt/backup/repositorio/ < /dev/null &
echo $$ > $pidfile
fi
Hope this helps!!!
In linux (I use a Ubuntu), I run a (ruby) program that continually runs all day long. My job is to monitor to see if the program fails and if so, re-launch the program. This consists up simply hitting 'Up' for last command and 'Enter'. Simple enough.
There has to be a way to write a bash script to monitor my program if its stops working and to re-launch it automatically.
How would I go about doing this?
A bonus is to be able to save the output of the program when it errors.
What you could do:
#!/bin/bash
LOGFILE="some_file.log"
LAUNCH="your_program"
while :
do
echo "New launch at `date`" >> "${LOGFILE}"
${LAUNCH} >> "${LOGFILE}" 2>&1 &
wait
done
Another way is to periodicaly check the PID:
#!/bin/bash
LOGFILE="some_file.log"
LAUNCH="your_program"
PID=""
CHECK=""
while :
do
if [ -n "${PID}" ]; then
CHECK=`ps -o pid:1= -p "${PID}"`
fi
# If PID does not exist anymore, launch again
if [ -z "${CHECK}" ]; then
echo "New launch at `date`" >> "${LOGFILE}"
# Launch command and keep track of the PID
${LAUNCH} >> "${LOGFILE}" 2>&1 &
PID=$!
fi
sleep 2
done
Infinite loop:
while true; do
your_program >> /path/to/error.log 2>&1
done
Here is my code:
#!/bin/bash
ps cax | grep testing > /dev/null
while [ 1 ]
do
if [ $? -eq 0 ]; then
echo "Process is running."
sleep 10
else
nohup ./testing.sh &
sleep 10
fi
done
I run it as nohup ./script.sh &
and it said nohup: failed to run command './script.sh': No such file or directory
What is wrong?
The file script.sh simply does not exist in the directory that you are issuing the command from.
If it did exist and was not executable you would get:
`nohup: failed to run command ‘./script.sh’: Permission denied
For each newly created scripts on Linux, you should first change the permission as you can see the permission details by using
ls -lah
The following content may help you:
#!/bin/bash
while [ 1 ];
do
date=`date`
pid=`ps -ef | grep "your process" | grep -v grep | awk -F' ' '{print $2}'`
if [[ -n $pid ]]; then
echo "$date - processID $pid is running."
else
echo "$date - the process is not running"
# script to restart your process
say: start the process
fi
sleep 5m
done
Make sure your script is saved as script.sh
and your executing nohup ./script.sh & from the same directory in which script.sh.
Also you can give executable permission for script.sh by
chmod 776 script.sh
or
nohup ./script.sh &
Run as
nohup sh ./script.sh &
I'm trying to call a custom shell script through sh:
/bin/sh -c 'myscript.sh` >log.txt 2>&1 & echo $!
Output of this command is a PID of a created background process. I want to instruct /bin/sh to save return code of myscript.sh to some file. Is it possible?
echo $? >> /path/to/return_code
$? has the return code of the last statement in bash.
(/bin/sh -c "myscript.sh" >log.txt 2>&1 ; echo $? >somefile) & echo $!
(
/bin/sh -c 'myscript.sh` >log.txt 2>&1
echo $? > some_file
) &