Get A String In Shell/python Using Sys.argv

I'm beginning with bash and I'm executing a script : $ ./readtext.sh ./InputFiles/applications.txt Here is my readtext.sh code : #!/bin/bash filename='$1' counter=1 while IFS=: t

Solution 1:

It is easier for you to pass the parameter "$1" to the internal command python3.

If you don't want to do that, you can still get the external command line parameter with the trick of /proc, for example:

$ cat parent.sh 
#!/usr/bin/bash

python3 child.py
$ cat child.py
import os

ext = os.popen("cat /proc/" + str(os.getppid()) + "/cmdline").read()
print(ext.split('\0')[2:-1])
$ ./parent.sh aaaa bbbb
['aaaa', 'bbbb']

Note:

1. the shebang line in parent.sh is important, or you should execute ./parent.sh with bash, else you will get no command line param in ps or /proc/$PPID/cmdline.
2. For the reason of [2:-1]: ext.split('\0') = ['bash', './parent.sh', 'aaaa', 'bbbb', ''], real parameter of ./parent.sh begins at 2, ends at -1.

Update: Thanks to the command of @cdarke that "/proc is not portable", I am not sure if this way of getting command line works more portable:

$ cat child.py
import os

ext = os.popen("ps " + str(os.getppid()) + " | awk ' { out = \"\"; for(i = 6; i <= NF; i++) out = out$i\" \" } END { print out } ' ").read()
print(ext.split(" ")[1 : -1])

which still have the same output.

Solution 2:

This is the python file that you can use in ur case

import sys

file_name = sys.argv[1]

with open(file_name,"r") as f:
    data = f.read().split("\n")

print("\n".join(data))

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