Wy can't Powershell display a string when i use stdout in Python?

user_13597101 0
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It runs fine in VS Code, but in powershell it does prompt user input but without displaying the string in "stdout". Here is the sample piece of code:

import sys


def get_int():
    sys.stdout.write("Enter number(s). ")
    return map(int, sys.stdin.readline().strip().split())


def get_float():
    sys.stdout.write("Enter number(s). ")
    return map(float, sys.stdin.readline().strip().split())


def get_list_of_int():
    sys.stdout.write("Enter numbers followed by space. ")
    return list(map(int, sys.stdin.readline().strip().split()))


def get_string():
    sys.stdout.write("Enter string. ")
    return sys.stdin.readline().strip()


a, b, c, d = get_int()
e, f, g = get_float()
arr = get_list_of_int()
str = get_string()
powershell python
1 Answers

Why can't Powershell display a string when i use stdout in Python?

Because the stdout device interface may buffer writes to it, so either run python in unbuffered mode:

PS C:\> python -u script.py

or explicitly flush the buffer before reading stdin:

def get_int():
    sys.stdout.write("Enter number(s). ")
    sys.stdout.flush()
    return map(int, sys.stdin.readline().strip().split())

or you can replace sys.stdout with a wrapper that does it for you:

class Unbuffered(object):
   def __init__(self, stream):
       self.stream = stream
   def write(self, data):
       self.stream.write(data)
       self.stream.flush()
   def writelines(self, datas):
       self.stream.writelines(datas)
       self.stream.flush()
   def __getattr__(self, attr):
       return getattr(self.stream, attr)

sys.stdout = Unbuffered(sys.stdout)

# this will now flush automatically before calling stdin.readline()
sys.stdout.write("Enter something: ")
numbers = map(int, sys.stdin.readline().strip().split())
user_7126490
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