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How to delete lines from a file in PERL?

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# 1  
Old 10-08-2011
How to delete lines from a file in PERL?
Hi,

I have 500 MB of file.

I want to retain first line and last line of the file.

I am unaware of deleting lines from a file in PERL.

How can i do it in PERL?

Regards
VANITHA
# 2  
Old 10-08-2011
hope this helps
Code:
http://www.perlmonks.org/?node_id=349106

# 3  
Old 10-08-2011
Quote:
Originally Posted by vanitham
...
I have 500 MB of file.
I want to retain first line and last line of the file.
...How can i do it in PERL?
...
For a file of that size the shell's head/tail commands should be much faster than opening and iterating through it using Perl.
I'd do something like -

Code:
(head -1 myfile >myfile.tmp; tail -1 myfile >>myfile.tmp) && mv myfile.tmp myfile

tyler_durden
# 4  
Old 10-08-2011
Sed way ..
Code:
$ sed -n '1p;$p' infile > infile.tmp

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