Need help on Python File write operation.....

[Devil]

Hi,

I am stuck at below mention point. I am not able to find any way of doing it
in python. I have google enough to find any sample code but unsuccessful.
Plz help.

I am trying to write a file of size (user specified size) so that it will
pops(remove) the oldest line written (data item) to make room for newest
line (data item ) when max size is reached. I also want to see data update
while program running (some thing like flush() because file size some time
is very huge... so need to check the data copying to file)

Data written in file is a string (array of data of variable length ) ended
by '\n'.

Do help me as it is very urgent for me.

Thanks in advance.

Regards,
jaing
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File parser

[Angelic Devil]

I'm building a file parser but I have a problem I'm not sure how to
solve.  The files this will parse have the potential to be huge
(multiple GBs).  There are distinct sections of the file that I
want to read into separate dictionaries to perform different
operations on.  Each section has specific begin and end statements
like the following:

KEYWORD
.
.
.
END KEYWORD

The very first thing I do is read the entire file contents into a
string.  I then store the contents in a list, splitting on line ends
as follows:


file_lines = file_contents.split('\n')


Next, I build smaller lists from the different sections using the
begin and end keywords:


begin_index = file_lines.index(begin_keyword)
end_index = file_lines.index(end_keyword)
small_list = [ file_lines[begin_index + 1] : file_lines[end_index - 1] ]


I then plan on parsing each list to build the different dictionaries.
The problem is that one begin statement is a substring of another
begin statement as in the following example:


BAR
END BAR

FOOBAR
END FOOBAR


I can't just look for the line in the list that contains BAR because
FOOBAR might come first in the list.  My list would then look like

[foobar_1, foobar_2, ..., foobar_n, ..., bar_1, bar_2, ..., bar_m]

I don't really want to use regular expressions, but I don't see a way
to get around this without doing so.  Does anyone have any suggestions
on how to accomplish this? If regexps are the way to go, is there an
efficient way to parse the contents of a potentially large list using
regular expressions?

Any help is appreciated!

Thanks,
Aaron

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 remove all doubt."
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Re: File parser

[Angelic Devil]

"Rune Strand" <[EMAIL PROTECTED]> writes:


Thanks.  This shows definate promise.  I've already tailored it for
what I need, and it appears to be working.


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state, is but a necessary evil; in its worst state, an intolerable one."
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Record separator for readlines()

[Angelic Devil]

I know this has been asked before (I already consulted the Google
Groups archive), but I have not seen a definative answer.  Is there a
way to change the record separator in readlines()?  The documentation
does not mention any way to do this.  I know way back in 1998, Guido
said he would consider adding it, but apparently that didn't happen.
Is there some way to do this?

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then you win."
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