optimized sed

sed '/foo/ s/foo/foobar/g' <filename>
Use optimized sed to big file/stream to reduce execution time Use sed '/foo/ s/foo/foobar/g' <filename> insted of sed 's/foo/foobar/g' <filename>

-6
By: totti
2013-01-02 08:52:44

These Might Interest You

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    1
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  • Same as the cool matrix style command ( http://www.commandlinefu.com/commands/view/3652/matrix-style ), except replacing the printed character with randomness. The command mentioned is much faster and thus more true to the matrix. However, mine can be optimized, but I wasted ... i mean spent enough time on it already Show Sample Output


    6
    check the sample output below, the command was too long :(
    pykler · 2009-09-29 19:30:10 2
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    5
    cc -march=native -E -v - </dev/null 2>&1 | grep cc1
    manny79 · 2009-08-21 09:47:37 3
  • Ok so it's rellay useless line and I sorry for that, furthermore that's nothing optimized at all... At the beginning I didn't managed by using netstat -p to print out which process was handling that open port 4444, I realize at the end I was not root and security restrictions applied ;p It's nevertheless a (good ?) way to see how ps(tree) works, as it acts exactly the same way by reading in /proc So for a specific port, this line returns the calling command line of every thread that handle the associated socket


    -5
    p=$(netstat -nate 2>/dev/null | awk '/LISTEN/ {gsub (/.*:/, "", $4); if ($4 == "4444") {print $8}}'); for i in $(ls /proc/|grep "^[1-9]"); do [[ $(ls -l /proc/$i/fd/|grep socket|sed -e 's|.*\[\(.*\)\]|\1|'|grep $p) ]] && cat /proc/$i/cmdline && echo; done
    j0rn · 2009-04-30 12:39:48 1

What Others Think

Not usefull : No effect with a 3000 lines file.
Zulu · 284 weeks and 6 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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