I am trying to create screens and run python script using bash. The script works fine in local. But, when I run the same script in the server, screens are getting created but python script is not executing in some screens. Any issues with the code?
#!/bin/bash
inc=9
end=$(expr "$2" + "$inc")
for i in $(seq -w "$2" $end)
do
screen -dmS "$1$i" bash
screen -r "$1$i" -p 0 -X exec python test.py
done
And I execute as sh auto_start.sh pyt 1
Related
I'm trying to controll my Roomba vacuum cleaner by a RaspberryPi. But still having some problems.
I need to send a special command to the serial interface to start the vacuum cleaner. If I do this in the Bash it works fine:
echo -n -e "\x87" > /dev/ttyAMA0
If I put this in my shell script it does not work any more:
#! /bin/bash
echo -n -e "\x87" > /dev/ttyAMA0
Any idea?
Have you made the script runnable? I.E. chmod +x script.sh. Also make sure you are running the script correctly ./script.sh. For more help see this website.
i am currently working on a little bash script to start a .py file in a Screen session and could use help.
I have these 2 Files:
test.py (located at /home/developer/Test/):
import os
print("test")
os.system("ping -c 5 www.google.de>>/home/developer/Test/test.log")
test.sh (located at /home/developer/):
#!/bin/bash
Status="NULL"
if ! screen -list | grep -q "foo";
then
Status="not running"
else
Status="running"
fi
echo "Status: $Status"
read -p "Press [Enter] key to start/stop."
if [[ $Status == "running" ]]
then
screen -S foo -p 0 -X quit
echo "Stopped Executing"
elif [[ $Staus == "not running" ]]
then
screen -dmS foo sh
screen -S foo -X python /home/developer/Test/test.py
echo "Created new Instance"
else
exit 1
fi
It works as intendet until it has to start the python script aka. this line:
screen -S foo -X python /home/developer/Test/test.py
when running it in my normal shell i get:
test
sh: 1: cannot create /home/developer/Test/test.log: Permission denied
MY Questions:
I understand the cause of the Permission denied case (works with sudo) but how do i give Permissions and more interestingly, to whom do i give the Permissions to? (python? | screen? | myuser?)
Is the line to create a new instance in which the script runs correct like that?
Can u think of a better way to execute a python script which has to run night and day but is start and stoppable and doesn't block the shell?
To answer your questions:
You should not need to use sudo at all if the proper user/group is set on the scripts.
$ chmod 644 <user> <group> <script name>
The line creating the new instance does not look correct, it should be more like:
screen -S foo -d -m /usr/bin/python /home/Developer/Test/test.py
While using full path to the python exec; remove useless preceding line: screen -dmS foo sh
Screen is more than adequte to prefer such tasks.
Other problems in your script:
Add a shebang to the python script (eg. #!/usr/bin/python)
Typo on line 20 of test.sh: should be $Status, not $Staus
You may need to initially create test.log before executing your script (eg. touch test.log)
Consider the following shell script on example.com
#/bin/bash
export HELLO_SCOPE=WORLD
eval $#
Now, I would like to download and then execute this shell script with parameters in the simplest way and be able to launch an interactive bash terminal with the HELLO_SCOPE variable set.
I have tried
curl http://example.com/hello_scope.sh | bash -s bash -i
But it quits the shell immediately. From what I can understand, it's because curls stdout, the script, remains the stdin of the bash, preventing it from starting interactively (as that would require my keyboard to be stdin).
Is there a way to avoid this without going through the extra step of creating a temporary file with the shell script?
You can source it:
# open a shell
. <(curl http://example.com/hello_scope.sh)
# type commands ...
You could just download this script you (using wget for example) and source this script, isn't it ?
script_name="hello_scope.sh"
[[ -f $script_name ]] && rm -rf "$script_name"
wget "http://example.com/$script_name" -O "$script_name" -o /dev/null
&& chmod u+x "$script_name"
&& source "$script_name"
You could use . "$script_name" instead of source "$script_name" if you want (. is POSIX compliant). You could write the previous code in a script and source it to have interactive shell with the setted variable $HELLO_SCOPE.
Finally you could remove the eval line in your remote shell script.
I am looking into running matlab script in Linux similar to bash/python scripts. I.e., a matlab script that can be run as an application.
You can get a similar effect without your custom mash script by adding the following header to the files you want to be executable:
#/usr/bin/bash
/path/to/matlab -r "$(sed -n -e '4,$p' < "$0")"
exit $?
If you want matlab to terminate after executing the script, as in your example, you could replace the second line with
sed -n -e '4,$p' < "$0" | /path/to/matlab
The idea here is to execute a bash command that simply clips off the header of the script, and passes the rest along to matlab.
Here is the implementation I came up with -
Create /usr/bin/mash script file containing the following lines -
#!/bin/bash
grep -ve '^(#!\|^\s*$)' ${#: -1} | ${#: 1:$#-1}
exit $?
Make mash script executable -
$ chmod +x /usr/bin/mash
Write matlab script file called test.msh
#!/usr/bin/mash /usr/local/MATLAB/R2012a/bin/matlab -nodisplay
format long
a = 2*pi % matlab commands ...
Make test.msh script executable -
$ chmod +x mash
Run test.msh
$ ./test.msh
...
>> >> a =
6.283185307179586
I have a script (say run.py) and I want to scp that to a remote machine (say 10.1.100.100), cd into a directory in that remote machine, and execute run.py in that directory.
How do I wrap the above procedure in one single bash script? I don't know how to let bash execute commands remotely in another machine.
Hopefully I can see that stdout of run.py in my terminal. But if I can only redirect it, that's fine as well.
chmod +x ./run.py
scp -pq ./run.py 10.1.100.100:'/home/myremotedirectory/run.py'
ssh 10.1.100.100 'cd /somedirectory && /home/myremotedirectory/run.py'
See if that helps
How to run a local script over SSH
Synopsis:
Script execution over SSH without copying script file.
You need a simple SSH connexion and a local script.
Code:
#!/bin/sh
print_usage() {
echo -e "`basename $0` ssh_connexion local_script"
echo -e "Remote executes local_script on ssh server"
echo -e "For convinient use, use ssh public key for remote connexion"
exit 0
}
[ $# -eq "2" ] && [ $1 != "-h" ] && [ $1 != "--help" ] || print_usage
INTERPRETER=$(head -n 1 $2 | sed -e 's/#!//')
cat $2 | grep -v "#" | ssh -t $1 $INTERPRETER
Examples:
- ssh-remote-exec root#server1 myLocalScript.sh #for Bash
- ssh-remote-exec root#server1 myLocalScript.py #for Python
- ssh-remote-exec root#server1 myLocalScript.pl #for Perl
- ssh-remote-exec root#server1 myLocalScript.rb #for Ruby
Step by step explanations
This script performs this operations:
1° catches first line #! to get interpreter (i.e: Perl, Python, Ruby, Bash interpreter),
2° starts remote interpeter over SSH,
3° send all the script body over SSH.
Local Script:
Local script must start with #!/path/to/interpreter
- #!/bin/sh for Bash script
- #!/usr/bin/perl for Perl script
- #!/usr/bin/python for Python script
- #!/usr/bin/ruby for Ruby script
This script is not based on local script extension but on #! information.
You can do it like this:
ssh -l yourid 10.1.100.100 << DONE
cd /your/dir/
./run.py
DONE
Above has been edited, I don't remember what it was like originally, if I want to do it in one single connection, I will do it this way.
ssh -l yourid 10.1.100.100 python < <(
echo "import os"
echo "os.chdir('/yourdir')"
echo "print(os.getcwd())"
cat yourscript.py
)
Remember, that this is not a rule, that you HAVE TO cd to the requested directory.
Once you get access to the remote machine, just type a relative path to this file, without using cd:
/some_folder/./run.py