This question already has answers here:
Equivalent of Bash Backticks in Python [duplicate]
(11 answers)
Closed 8 years ago.
As far as you know, we can use OS console commands, (For example dir,time and format in Windows) in Python programing using os.system('TheCommand') module. But this function return the state of Operation (0 for successful and 1 for failed).
I want to know if is there any way to use the output of the commands in the next commands? I mean (For example) I run os.system('dir') and save the list of directories in a variable!
This is fairly easy to do. Here I define the working directory and the edit time of a file as variables which I used later in my script.
#!/usr/bin/env python
PWD = os.getcwd()
edit_time=os.path.getmtime(file.txt)
Related
This question already has answers here:
How do I execute a string containing Python code in Python?
(14 answers)
Closed 1 year ago.
Is it possible to run a String text?
Example:
str = "print(2+4)"
Something(str)
Output:
6
Basically turning a string into code, and then running it.
Use exec as it can dynamically execute code of python programs.
strr = "print(2+4)"
exec(strr)
>> 6
I will not recommend you to use exec because:
When you give your users the liberty to execute any piece of code with the Python exec() function, you give them a way to bend the rules.
What if you have access to the os module in your session and they borrow a command from that to run? Say you have imported os in your code.
Sure is, looks like your "Something" should be exec.
str = "print(2+4)"
exec(str)
Check out this previous question for more info:
How do I execute a string containing Python code in Python?
This question already has answers here:
What is double dot(..) and single dot(.) in Linux?
(4 answers)
Closed 2 years ago.
using the command ~ls allows you to list files, which is difference if I add dot ~ls . ?
sorry for my english, I am practicing
dot shows the folder you are in. If u re in downloads. ls . shows downloads. In your situation, ls (without a directory argument) is going to list directories and files under the current directory(pwd).
This question already has answers here:
Propagate all arguments in a Bash shell script
(12 answers)
Closed 2 years ago.
I am trying to load Data frame into file but not able to get exact match. Can you please help me on this?
example:
"From...............\"dawood\"...........\"oral use\"........"
but i am getting:
"From................\"dawood\"...........\\"oral use\\\"......"
i am using below code to write the dataframe:
df.repartition(1).write.format('com.databricks.spark.csv').mode('overwrite').save(output_path,quote='"', sep='|',header='True',nullValue=None)
Can you please help me how to get exact match for all the reords.
either just copy this inside your shell script:
python imed_consump.py 'Smart Source'
but then your parameter is always fixed. should this not be desired, then do following inside shell
python imed_consump.py "$1"
and execute your shell like:
bash imed_consump.sh 'Smart Source'
This question already has answers here:
Store output of subprocess.Popen call in a string [duplicate]
(15 answers)
Closed 3 years ago.
I have to run a shell command from python and get the output of that command into a python variable
python_var = subprocess.check_output('/opt/PPPP/QQQ/my_cmd -option1 -option2 /opt/XXXX/YYYY/ZZZZZ/my_file')
You need to hand-split the arguments into a sequence, not just pass a string (passing a whole string requires shell=True on Linux, but introduces all sorts of security/stability risks):
python_var = subprocess.check_output(['/opt/PPPP/QQQ/my_cmd', '-option1', '-option2', '/opt/XXXX/YYYY/ZZZZZ/my_file'])
This question already has answers here:
Capture stdout from a script?
(11 answers)
Closed 3 years ago.
I'm trying to get a already written line in python 3, but I haven't found any function that can read a line from the terminal. It should work something like sys.stdout.read(), or sys.stdout.readline() but this function just throws an error.
If you mean to read from the user/a pipe, then simply use input.
However, from your comments it seems like you want to be able to read from what has already been printed.
To do this, you have a few options. If you don't actually want it to display on the terminal, and you only care about certain part of the output, then you can use contextlib.redirect_stdout and contextlib.redirect_stderr. You can combine this with io.StringIO to capture the output of your application to a string. This has been discussed in the question Capture stdout from a script in Python
However, if you want to have something which provides you both a means of printing to the terminal and giving you the lines, then you will need to implement your own type which inherits from io.TextIOBase or uses io.TextIOWrapper.
Do you mean something like this?
name = input("Enter a name: ")
print(name)