find added or deleted line in a file

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

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Re: find added or deleted line in a file by Anonymous Monk on Apr 21, 2011 at 08:44 UTC
I have a file say "f1" with ten line and I found that line no 7 has been added or say deleted so how can i get that line into another file can any1 let me know please Thanks! Let me understand, you have sucessfully opened a file, read lines, and found that the 7th line has been added or deleted, but you don't know how to get that line into another file? That sounds impossible, have you understood perlintro?	[reply]
Re: find added or deleted line in a file by pajout (Curate) on Apr 21, 2011 at 08:31 UTC
Please, show us your code, monks like to advice, but not like to work just for work.	[reply]
Re: find added or deleted line in a file by anonymized user 468275 (Curate) on Apr 21, 2011 at 09:47 UTC
Extract line 7 from fred to bert `perl -ne '$fh = ( $.==7 ? STDERR : STDOUT ); print $fh $_;' < fred >tm +p 2>bert; mv tmp fred` [download] Insert at line 7 in fred from another file bert `perl -ne '$.==7 and system("cat bert");print $_;' < fred >tmp; mv tmp +fred` [download] One world, one people	[reply] [d/l] [select]