Re^2: Print some lines in a range

Folks thanks a lot for your answers you saved my Soul & the best solution is the one that ikegami post

time perl -ne"next if $.<41901; print; exit if $.==50001;" data02.log > data03.log

real 0m0.26s

The next one also works but is slower to run

time perl -ne "print if 41901 .. 50001" data02.log > data03.log

real 0m33.21s

An this one runs too but it takes a lot of time to run

time perl -e"@lines=<>; print @lines[41900..50000];" data02.log > data03.log

real 1m9.42s

Comment on Re^2: Print some lines in a range Select or Download Code

Replies are listed 'Best First'.
Re^3: Print some lines in a range by ikegami (Patriarch) on Mar 06, 2010 at 23:19 UTC
The first stops when enough has been read. Both the second and the third read the entire file. The difference is that the third loads the entire file into memory. And since we're talking about at least 50,000 lines, you might be running into swapping issues. The third definitely has a lot more memory allocations (one per line) than the second (almost none), and those aren't cheap.	[reply]