f.read空了

Question

I'm doing all this in the interpreter..

loc1 = '/council/council1'
file1 = open(loc1, 'r')

at this point i can do file1.read() and it prints the file's contents as a string to standard output

but if i add this..

string1 = file1.read()

string 1 comes back empty.. i have no idea what i could be doing wrong. this seems like the most basic thing!

if I go on to type file1.read() again, the output to standard output is just an empty string. so, somehow i am losing my file when i try to create a string with file1.read()

Answer 1

You can only read a file once. After that, the current read-position is at the end of the file.

If you add file1.seek(0) before you re-read it, you should be able to read the contents again. A better approach, however, is to read into a string the first time and then keep it in memory:

loc1 = '/council/council1'
file1 = open(loc1, 'r')
string1 = file1.read()
print string1

Answer 2

You do not lose it, you just move offset pointer to the end of file and try to read some more data. Since it is the end of the file, no more data is available and you get empty string. Try reopening file or seeking to zero position:

f.read()
f.seek(0)
f.read()

Answer 3

Using with is the best syntax to use because it closes the connection to the file after using it(since python 2.5):

with open('/council/council1', 'r') as input_file:
   text = input_file.read()
print(text)

Answer 4

make sure your location is correct. Do you actually have a directory called /council under your root directory ( / ) ?. also use, os.path.join() to create your path

loc1 = os.path.join("/path","dir1","dir2")