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Shell Programming and Scripting

retain last 1000 line in a file

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# 8  
Old 05-11-2010
If you go for "tail" first run a quick test to see if your tail command is suitable.

Code:
tail -1000 filename | wc -l

Hopefully the answer is 1000 .
# 9  
Old 05-11-2010
Thank you Very much Curleb, for that detailed explanation and info. I should be going with tail. That will solve my purpose..
Also thank you Reebot and Methyl for your answers ..

Many Thanks & Regards.
# 10  
Old 05-11-2010
You can edit a file in place with ed. To delete all but the last 1000 lines:
Code:
ed -s file <<'EOF'
1,-1000d
wq
EOF

or, more clumsily
Code:
printf '1,-1000d\nwq\n' | ed -s file

Regards,
Alister
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