Commands by buffer (2)

  • Well this can come handy , when you don't feel like playing with pid rather if you know the process name say "firefox",it would kill it.The script given below would kill the process with its name given as first parameter , though not robust enough to notify that process doesn't exist , well if you know what you are doing that's wouldn't be a problem.:) ---- killhim.sh ---- #!/bin/bash ps -u $USER |grep $1 | awk '{ print $1}'| xargs kill ----


    -4
    ps -u $USER |grep $1 | awk '{ print $1}'| xargs kill
    buffer · 2009-07-20 10:06:32 8
  • The -p parameter tell the netstat to display the PID and name of the program to which each socket belongs or in digestible terms list the program using the net.Hope you know what pipe symbol means! Presently we wish to only moniter tcp connections so we ask grep to scan for string tcp, now from the op of grep tcp we further scan for regular expression /[a-z]*. Wonder what that means ? If we look at the op of netstat -p we can see that the name of the application is preceded by a / ( try netstat -p ) so,now i assume application name contains only characters a to z (usually this is the case) hope now it makes some sense.Regular expression /[a-z]* means to scan a string that start with a / and contains zero or more characters from the range a-z !!. Foof .. is t Show Sample Output


    -4
    while true; do netstat -p |grep "tcp"|grep --color=always "/[a-z]*";sleep 1;done
    buffer · 2009-07-16 04:52:49 4

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Install pip with Proxy
Installs pip packages defining a proxy

copy timestamps of files from one location to another - useful when file contents are already synced but timestamps are wrong.
Sometimes when copying files from one place to another, the timestamps get lost. Maybe you forgot to add a flag to preserve timestamps in your copy command. You're sure the files are exactly the same in both locations, but the timestamps of the files in the new home are wrong and you need them to match the source. Using this command, you will get a shell script (/tmp/retime.sh) than you can move to the new location and just execute - it will change the timestamps on all the files and directories to their previous values. Make sure you're in the right directory when you launch it, otherwise all the touch commands will create new zero-length files with those names. Since find's output includes "." it will also change the timestamp of the current directory. Ideally rsync would be the way to handle this - since it only sends changes by default, there would be relatively little network traffic resulting. But rsync has to read the entire file contents on both sides to be sure no bytes have changed, potentially causing a huge amount of local disk I/O on each side. This could be a problem if your files are large. My approach avoids all the comparison I/O. I've seen comments that rsync with the "--size-only" and "--times" options should do this also, but it didn't seem to do what I wanted in my test. With my approach you can review/edit the output commands before running them, so you can tell exactly what will happen. The "tee" command both displays the output on the screen for your review, AND saves it to the file /tmp/retime.sh. Credit: got this idea from Stone's answer at http://serverfault.com/questions/344731/rsync-copying-over-timestamps-only?rq=1, and combined it into one line.

replace a character/word/string in a file using vim
Replace all ocurrences in the file. The g option is to replace more than one occurrence in the same line. Whitout the g option, it only replace the first occurrence in the line.

Rename files in batch

compare two Microsoft Word documents
http://meld.sourceforge.net/ http://www.winfield.demon.nl/

Shell function to exit script with error in exit status and print optional message to stderr
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Drop or block attackers IP with null routes
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Encode a file to MPEG4 format
Encode video.avi into newvideo.avi using the libav codec to produce an MPEG4 file with a bitrate of 800

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