Code giving error

#1

with open(“sid.txt”,“w+”) as f:
f.write(“ajay siddartha”)
print(f.read())

this is not runnung

#2

hey @ajaysiddartha ,
is it giving any error ? or just not printing anything ?

#3

not printing anything

#4

you can’t do this like this , when you are using w+ as the operation to open file, you can write in it. You can’t read it then.

But if you change this operation to r then you will get the correct output.

#5

but w+ should do both the things no

#6

Yea you are right.
if you still to work with the same code , then you need to add a line f.seek(0) , it means while you have written to the file , then you are currently at the end of file , means if we read now we won’t get anything.
So for that we need to get at the first position, so we do so , and hence now we can read easily.

#7

with open(“sid.txt”,“w+”) as f:
f.seek(0)
f.write(“ajay siddartha”)
print(f.read())

even not primting

#8

no do it like.

with open(“sid.txt”,“w+”) as f:
>>> f.write(“ajay siddartha”)
>>> f.seek(0)
>>> print(f.read())

it will work.

#9

yes now working …but why it was not working in the below way

with open(“sid.txt”,“w+”) as f:
f.seek(0)
f.write(“ajay siddartha”)
print(f.read())

#10

because in this still we are end of the file before reading.
you need to place the seek call correctly

#11

but seek is coming before read function no…before reading it should move the cursor to start point

#12

after write function and before read

#13

ya thats ok but why not in that way…before reading ,everytime it will move the cursor to the starting point

#14

see , first you write “hello” , then your cursor will be at 5 position.
okay , so if you read then you won’t get anything.
but now, if we do f.seek(0) , then this will move the cursor to starting.
so now if you will read , then you can read directly as f.read() and it works.

#15

ok understood…and one more thing will the data inside file will be saved when the file is closed

#16

yes , it will be saved.

#17

so everytime this is ran ,the write function will run …
so will not the text append again and again?
if not then why?

#18

there are multiple methods to perform while opening a file.
So, when we use w or w+, then it will first empty the file and then will again write the text you do using write.

for appending you can use , a

#19

with open(“sid.txt”,“w+”) as f:

f.write("ajay siddartha")
f.seek(0)

print(f.read())

with open(“sid.text”,“a”) as f:
f.write(“siddartha ajay”)

with open(“sid.text”,“r”) as f:
print(f.read())

so we have to do this for appending and reading it

#20

Yeah its correct but after the above code, your cursor will be at beginning , so your second call will overwrite the first one.