The seek position is a byte index into the contents of the file similar to an array index. Its also interesting that if we open file in append mode 'a', we cannot seek to file's beginning.
The whence argument is optional and defaults to os.SEEK_SET or 0 (absolute file positioning); other values are os.SEEK_CUR or 1 (seek relative to the current position) and os.SEEK_END or 2 (seek relative to the file’s end). Say you would want to go 10 bytes back relative to your position:
If you create the necessary files on your computer, and run this .PY file, you will find that sometimes it works as desired, and other times it doesn't. Can anyone tell me how to seek to the end, or if there is a better solution to help me? This is a self-assigned challenge, so I don't appreciate giveaways, and just hints.
1 I am trying to understand how the seek function in python file handling works. The syntax of this function is seek (offset, whence). The parameter 'whence' is like a point of reference with possible values 0,1 and 2 referring to start of the file, current position of the pointer (return value of 'tell' function) and end of the file respectively.
Please explain the difference between Index Scan and Index Seek in MS SQL server with an sample example, since it will be helpful to know, what's the real use of it. Thanks in advance.
Every individual seek, scan, lookup, or update on the specified index by one query execution is counted as a use of that index and increments the corresponding counter in this view.
ok, here's how it goes. you have a variable last_pos, which contains the current byte offset from the beginning of the file. you open the file, seek() to that offset, then read a line using readline(). file pointer automatically advances to the beginning of the next line. then you use tell() to get the new offset and save it to the last_pos to ...
# seek by absolute position from start of the file fp.seek(last_read_byte) (fp is a python file object) I just thought that B) might start reading the file from the beginning. How do I check if that's the case? Should I worry about stupid things like this?
