how to pass variable from python to shell script when shell script is getting called inside python script

For passing only one argument, you can have a python script like this:

import subprocess
correctBc4jfiles = ["1","2","3"]
subprocess.call(["/bin/bash", "/path/to/mail.sh"] + correctBc4jfiles)

And have a bash script like this:

#!/bin/bash

# I want to know the number of files the correctBc4jfiles variable holds

echo "$#"

# I want to iterate this variable correctBc4jfiles. how will i iterate it in shell script.

for A in "$@"; do
    echo "$A"
done

# I want to assign the value of the correctBc4jfiles variable into another array variable which belongs to the shell script itself.

ANOTHER=("${@}")

# for A in "${ANOTHER[@]}"; do ...

Can we pass more than one variable from python to shell script? Like in this case we are passing only one variable correctBc4jfiles? How can I do this?

You have to make your python script pass the number of values for every variable as well like:

import subprocess

var0 = ["|1|", "|2|", "|3|"]
var1 = ["|4|", "|5|", "|6|"]

subprocess.call(["/bin/bash", "script.sh"] + [str(len(var0))] + var0 + [str(len(var1))] + var1)

And let bash interpret it:

#!/bin/bash

varprefix='var'
varindex=0

declare -i  count

while [[ $# -gt 0 ]]; do
    count=$1
    if [[ count -gt 0 ]]; then
        eval "${varprefix}$(( varindex++ ))=(\"\${@:2:count}\")"
        shift "$count"
    fi
    shift
done

set | grep ^var  ## Just show what variables were made.

It gives an output like this:

var0=([0]="|1|" [1]="|2|" [2]="|3|")
var1=([0]="|4|" [1]="|5|" [2]="|6|")
varindex=2
varprefix=var

So with that you could already use varX.

If you don't like the varX format, you could just copy the values to desired array variable:

myarray1=("${var0[@]}")
myarray2=("${var1[@]}")

You can:

• Step through the list, and then call mail.sh once for each file. This is the most reliable way.

• Convert the items in the list to a space delimited string, and then pass it in to mail.sh (assuming mail.sh is setup correctly, it should accept multiple arguments).

What you cannot do is pass ['a.txt','b.txt','c.txt'] wholesale to the script.