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Re: Fast editing of text file? [message #44477 is a reply to message #44476]

Wed, 15 June 2005 19:55

Andrew Cool
Messages: 219
Registered: January 1996

Senior Member

t_314159@yahoo.com wrote:
> Hi,
> I have a text file that I must access many times during program
> execution (1000's of times, really!) and I *always* only need to change
> the the text on the 12th line of the file. My question, how to
> efficiently access and alter the text of ONLY the 12th line without
> altering even a single space or comma on any of the rest of the lines?
> And did I mention fast since i've got to loop through this many times?

If lines[0:10] and lines[12:*] don't change, why not hold those
permanently
in memory as two string arrays, array_top and array_bottom.

Concoct Line 12 with your 3 new numbers,
and then printf to a new version of the file :-

printf,outlun, array_top ; lines 1..11
printf,outlun, line12 ; line 12
printf,outlun, array_bottom ; lines 13..end of file

This way you've only got 1 read, at the very start of your program, and
then 1 write per change of numbers.

Sounds easy.

Andrew C.

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[Message index]

		Re: Fast editing of text file? By: R.Bauer on Sun, 19 June 2005 01:12
		Re: Fast editing of text file? By: Craig Markwardt on Thu, 16 June 2005 07:51
		Re: Fast editing of text file? By: Michael Wallace on Thu, 16 June 2005 01:05
		Re: Fast editing of text file? By: Mark Hadfield on Wed, 15 June 2005 20:28
		Re: Fast editing of text file? By: Andrew Cool on Wed, 15 June 2005 19:55
		Re: Fast editing of text file? By: marc schellens[1] on Wed, 15 June 2005 00:55
		Re: Fast editing of text file? By: Michael Wallace on Tue, 14 June 2005 21:22
		Re: Fast editing of text file? By: t_314159 on Tue, 14 June 2005 17:15
		Re: Fast editing of text file? By: Michael Wallace on Tue, 14 June 2005 16:26

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