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Command to update last line.

 
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Top Forums UNIX for Dummies Questions & Answers Command to update last line.
# 8  
Old 08-10-2011
That's one of the clever mechanisms I always forget about and sometimes grab an array heh, thanks Smilie
# 9  
Old 08-11-2011
Thanks zaxxon and alister,

I tried the code, in the output I could see the last line is gone.. Also I think in this logic we are counting the lines in the file and then replacing it. Please correct me if I'm wrong.

Also I have the count, I don't want to traverse to count the lines. but I need to replace the record count with entirely different number. I mean the count which is in the last line, I hv to replace exactly that without counting. Please suggest.
thanks in advance.
# 10  
Old 08-11-2011
?? Somebody or something has to count - else how would you know with which value you'll have to substitute the old value with? For this, Alister's solution should be better suitable than mine, especially for big files.

But if you already know how many lines there are minus the header and footer, you can just substitute the value in the last line directly.
 
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