From: "Peña, Botp" <botp@...>
Date: 2008-06-05T10:16:46+09:00
Subject: Re: deleting first line from a file

From: suresh [mailto:suresh.amritapuri@gmail.com] 
# I have a HUGE data file multiple lines of data. I want to delete just
# the first line from it. How to do it efficiently?

i think you want something fast yet clean ruby solution.

maybe something like,

botp@botp-desktop:~$ cat test.txt
this line will be deleted
2nd line
3rd asdfasdf line
4th qwerty line
5th
6th six
7th 777777777777

botp@botp-desktop:~$ irb
irb(main):001:0> File.open("newfile","w") do |fw|
irb(main):002:1*   File.open("test.txt") do |fr|
irb(main):003:2*      fr.gets
irb(main):004:2>      fw.write fr.read
irb(main):005:2>   end
irb(main):006:1> end
=> 72

botp@botp-desktop:~$ cat newfile
2nd line
3rd asdfasdf line
4th qwerty line
5th
6th six
7th 777777777777


just add some checks/rescues so that it will work on all your cases.

kind regards -botp