filename = 'learning_python.txt'

with open(filename) as file_object:
    contents = file_object.read()
    print(contents.strip())

with open(filename) as file_object:
    lines = file_object.readlines()

for line in lines:
    print(line.strip())

with open(filename) as file_object:
    for line in file_object:
        print(line.rstrip())

filename = 'learning_python.txt'

with open(filename) as file_object:
    contents = file_object.read()
    print(contents.strip())
    for line in file_object:
        print(line.rstrip())
    lines = file_object.readlines()

for line in lines:
    print(line.strip())

(Jun-02-2018, 07:53 PM)woooee Wrote: After the first read() the file's pointer is positioned at the end of the file, so the "for line in file_object" starts at the end of the file, where there are no more records to be read. Take a look a seek() in the docs if you want to move the pointer back to the beginning of the file.

victor at Jerry in /m/s/A/M/Chill
↪ touch /tmp/test.txt
victor at Jerry in /m/s/A/M/Chill
↪ echo "onsones
  csicnsns
  snddddnsod
  jcsodncs" > /tmp/test.txt
victor at Jerry in /m/s/A/M/Chill
↪ cat /tmp/test.txt 
onsones
csicnsns
snddddnsod
jcsodncs
victor at Jerry in /m/s/A/M/Chill
↪ python
Python 3.6.4 (default, Jan  5 2018, 02:35:40) 
[GCC 7.2.1 20171224] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> with open('/tmp/test.txt', 'r') as f:
...     content = f.read()
...     print(content)
... 
onsones
csicnsns
snddddnsod
jcsodncs

>>> with open('/tmp/test.txt', 'r') as f:
...     lines = f.readlines()
... 
>>> for line in lines:
...     print(line)
... 
onsones

csicnsns

snddddnsod

jcsodncs

>>> with open('/tmp/test.txt', 'r') as f:
...     for line in f:
...         print(line.rstrip())
... 
onsones
csicnsns
snddddnsod
jcsodncs

(Jun-02-2018, 07:58 PM)wavic Wrote: I can't reproduce it. Here I am creating a file with some nonsenses in it and run Python. You can see that every time I get an output. Are you sure that this is the whole scenario and you don't miss something?

(Jun-02-2018, 08:03 PM)PythonZenon Wrote: The guy above answered correctly. Using seek(0) solved my problem. Thank you for your time :)

Output:
# test.txt
hello
world

filename = 'test.txt'
with open(filename) as file_object:
    print(id(file_object)) # memory location of file object
    contents = file_object.read()
    print(contents.strip())

with open(filename) as file_object:
    print(id(file_object)) # memory location of file object
    lines = file_object.readlines()
for line in lines:
    print(line.strip())

Output:
55480368
hello
world
55480496
hello
world

(Jun-02-2018, 08:31 PM)snippsat Wrote: The scenario @woooee talk about can occur,but it should occur in the code you posted.
Both second and third with open() will file object be overwritten in memory.

(Jun-02-2018, 07:39 PM)PythonZenon Wrote: (it prints contents of the file only once instead of thrice):

filename = 'learning_python.txt'
 
with open(filename) as file_object:
    contents = file_object.read()
    print(contents.strip())
    for line in file_object:
        print(line.rstrip())
    lines = file_object.readlines()
 
for line in lines:
    print(line.strip())

(Jun-02-2018, 09:11 PM)buran Wrote: I think OP is asking why this code is not printing the text file 3 times: