Python File handling: standard input and output - 


import sys   fileobject=open('file.txt','w')    fileobject.write(sys.stdin.readline()) cat

in above code, shouldn't cat in file after execution? however, when run it, find file empty. if code wrong, can explain how sys.stdin.read() , sys.stdout.write() work , uses?

you need close file

import sys   fileobject = open('file.txt', 'w')    fileobject.write(sys.stdin.readline()) cat fileobject.close()

if want see updated file content before closing file or exiting program can use flush():

fileobject.flush()

check stackoverflow question standard input/output


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