i got this list
commands = ['cd var','cd www','cd html','sudo rm -r folder']
I'm trying to execute one by one all the elements inside as a bash script, with no success. Do i need a for loop here?
how to achieve that?, thanks all!!!!
3 Answers
for command in commands:
os.system(command)
is one way you could do it ... although just cd'ing into a bunch of directories isnt going to have much impact
NOTE this will run each command in its own subshell ... so they would not remember their state (ie any directory changes or environmental variables)
if you need to run them all in one subshell than you need to chain them together with "&&"
os.system(" && ".join(commands)) # would run all of the commands in a single subshell
as noted in the comments, in general it is preferred to use subprocess module with check_call or one of the other variants. however in this specific instance i personally think that you are in a 6 to 1 half a dozen to the other, and os.system was less typing (and its gonna exist whether you are using python3.7 or python2.5 ... but in general use subprocess exactly which call probably depends on the version of python you are using ... there is a great description in the post linked in the comments by @triplee why you should use subprocess instead)
really you should reformat your commands to simply
commands = ["sudo rm -rf var/www/html/folder"] note that you will probably need to add your python file to your sudoers file
also Im not sure exactly what you are trying to accomplish here ... but i suspect this might not be the ideal way to go about it (although it should work...)
5 Comments
tripleee
This won't work because
cd var will run in a subprocess, then the next command runs in the (unchanged) directory of the parent Python process.
Joran Beasley
the condition that they all run in the same subshell was not stipulated ... but i can see how the OP would potentially desire that behaviour
tripleee
No, it wasn't spelled out, and probably the OP doesn't even realize this; but this is a common enough bug with subprocesses.
tripleee
Alao you should prefer
subprocess.run() or subprocess.check_call() over os.system(); see the post I linked from another comment above.Joran Beasley
none of the compelling reasons to do that apply here imho .... its really 6 to 1 half a dozen to the other ... in fact he is using commands that would require
shell=True so its pretty extra moot ... that said in general yes... this was just less typingThis is just a suggestion, but if your just wanting to change directories and delete folders, you could use os.chdir() and shutil.rmtree():
from os import chdir
from os import getcwd
from shutil import rmtree
directories = ['var','www','html','folder']
print(getcwd())
# current working directory: $PWD
for directory in directories[:-1]:
chdir(directory)
print(getcwd())
# current working directory: $PWD/var/www/html
rmtree(directories[-1])
Which will cd three directories deep into html, and delelte folder. The current working directory changes when you call chdir(), as seen when you call os.getcwd().
Comments
declare -a command=("cd var","cd www","cd html","sudo rm -r folder")
## now loop through the above array
for i in "${command[@]}"
do
echo "$i"
# or do whatever with individual element of the array
done
# You can access them using echo "${arr[0]}", "${arr[1]}" also
2 Comments
Joran Beasley
this is awesome :) I think they were asking how to do it in python but this is great! thanks!
Kalangu
A python list can be very easily imported in to bash stackoverflow.com/questions/26162394/…
cdcommands into one command, then use Bash's&&(and) operator:os.system("cd var/www/html/ && sudo rm -r folder")