fseek In Compressed Files

[Peter Otten]

Serhiy Storchaka wrote:

> 30.01.14 13:28, Peter Otten написав(ла):
>> Ayushi Dalmia wrote:
>>
>>> I need to randomly access a bzip2 or gzip file. How can I set the offset
>>> for a line and later retreive the line from the file using the offset.
>>> Pointers in this direction will help.
>>
>> with gzip.open(filename) as f:
>>      f.seek(some_pos)
>>      print(f.readline())
>>      f.seek(some_pos)
>>      print(f.readline())
>>
>> seems to work as expected. Can you tell a bit more about your usecase (if
>> it isn't covered by that basic example)?
> 
> I don't recommend to seek backward in compressed file. This is very
> inefficient operation.

Do you know an efficient way to implement random access for a bzip2 or gzip 
file?