in reply to Truncate the front of a file
Just change 1024 to whatever byte size you want ... you do have to have that much memory available, but the rest is line by line.perl -pi.bak -e'BEGIN{$/=\1024}($_,$/)=(undef,"\n")if ref$/' file.txt
UPDATE:
merlyn shared a better version in the CB shortly after i posted:
Reading the rest line by line is unecessary. Thanks again merlyn! :)perl -pi.bak -e'BEGIN{$/=\1024}($_,$/)=()if 1..1' file.txt
jeffa
L-LL-L--L-LL-L--L-LL-L-- -R--R-RR-R--R-RR-R--R-RR B--B--B--B--B--B--B--B-- H---H---H---H---H---H--- (the triplet paradiddle with high-hat)
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