When running the following python code:
>>> f = open(r"myfile.txt", "a+")
>>> f.seek(-1,2)
>>> f.read()
'a'
>>> f.write('
')
I get the following (helpful) exception:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
IOError: [Errno 0] Error
The same thing happens when openning with "r+".
Is this supposed to fail? Why?
Edit:
- Obviously, this is just an example, not what I am actually trying to execute. My actual goal was to verify that the files ends with "
", or add one, before adding the new lines.
- I am working under Windows XP, and they problem exists in both Python 2.5 and Python 2.6.
I managed to bypass the problem by calling seek() again:
f = open(r"myfile.txt", "a+")
f.seek(-1,2)
f.read()
'a'
f.seek(-10,2)
f.write('
')
The actual parameters of the 2nd seek call don't seem to matter.
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