Strange "IndexError: list index out of range" error. Python

Question

I have a program that need to use something like that:

file1=open("cliente\\config.ini","r")

print file1.read().split(",")

user=file1.read().split(",")[0]
passwd=file1.read().split(",")[1]
domain=file1.read().split(",")[2]
file1.close()

In the file there is 3 strings separated by a "," (user,pass,domain).

This is the output:

['user', 'pass', 'domain']
Traceback (most recent call last):
  File "C:\Users\default.default-PC\proyectoseclipse\dnsrat\prueba.py", line 8, in <module>
    passwd=file1.read().split(",")[1]
IndexError: list index out of range

I am taking the 0, 1 and 2 strings in the list so I am not taking one that does not exist.

So, why I am having an error??

Thank you very much.

Answer 1

You're reading past the end of the file. When you invoke read without arguments, the contents of the entire file are read and the pointer advances to the end of the file. What you want is to read once, and save the contents in a variable. Then, access indices from that:

file1 = open("cliente\\config.ini","r")

line1 = file1.read().split(",")

user = line1[0]
passwd = line1[1]
domain = line1[2]
file1.close()

Answer 2

file1=open("cliente\\config.ini","r")

data = file1.read().split(",")

user=data[0]
passwd=data[1]
domain=data[2]
file1.close()

Your first file.read() line will move the cursor to the end of the file after reading the line. Other file.read() won't read the file again as you expected. Instead it will read from the end of the cursor and that will return empty string.

Answer 3

read() is a methoe to get data from reading buffer. And you can't get data from buffer more than one time.

Answer 4

read() will return what's in the file. From the docs:

...which reads some quantity of data and returns it as a string.

If you call it again there won't be anything left to read.