Find all the missing paths in the PATH variable in bash script

Here is a simple script that will list out all the paths in the PATH variable that do not exist.

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      #!/bin/bash -<br /> #===============================================================================<br /> #<br /> #          FILE:  wrong_path.sh<br /> #<br /> #         USAGE:  ./wrong_path.sh<br /> #<br /> #   DESCRIPTION:  Show Directories in the PATH Which does NOT Exist<br /> #<br /> #       OPTIONS:  ---<br /> #  REQUIREMENTS:  ---<br /> #          BUGS:  ---<br /> #         NOTES:  ---<br /> #        AUTHOR:  Amit Agarwal (AKA), amit.agarwal@amit-agarwal.co.in<br /> #       COMPANY:  Individual<br /> #       VERSION:  1.0<br /> #       CREATED:  09/20/2009 09:15:48 AM IST<br /> #      REVISION:  ---<br /> #===============================================================================<br /> <br /> set -o nounset                              # Treat unset variables as an error<br /> <br /> (IFS=:;for p in $PATH; do test -d $p || echo $p; done)
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bash 4.0 – new feature mapfile

Recently I encountered a problem where I had to create couple of arrays in bash and these were quite dynamic in nature. This script was supposed to be used by couple of guys whom I did not trust too much in opening the script and modifyikng the array. So, the solution was to put these in different files and then put them in array using bash script itself. This is when I went through the bash man page again and found an interesting new inbuilt mapfile

perl is faster than bash in some cases.

Some days back, I had to generate some data to be uploaded to a database. As usual I assumed that bash should be faster and hence wrote the script to create the files in bash. But I found that even after 5 hours I was only 10% done with the data generation. Now that would mean that it would take around 50 hours to complete the data generation. Something did not look correct to me and I asked one of my colleague. He suggested I do a strace.

Install a fully functional terminal server capable of accepting connections from RDP(Windows).

Inoformation on xrdp:

The goal of this project is to provide a fully functional Linux terminal server, capable of accepting connections from rdesktop and Microsoft’s own terminal server / remote desktop clients.

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      &nbsp;sudo yum install xrdp
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There is not much configuration needed for this so I will not go into details. If you are stuck with something though, you can ask in the comments for the post.

List all installed rpm packages and it’s size

If you are looking for a command to see the disk usage by each of the rpm‘s then you can use this command:

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      &nbsp;rpm -q --queryformat "%10{SIZE}\t%{NAME}\n"
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And if you use this command very regularly then you can create an alias like

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      &nbsp;alias rpm_size='rpm -q --queryformat "%10{SIZE}\t%{NAME}\n" '
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and use it like

New feature in Gnome/Nautilus

One of the things that I never realized that I am missing in Nautilus until they put the feature in was this. When a file is being copied and there is conflict, there should be option to rename the new file being copied. Also, if the file being copied is image then a small preview/thumbnail would be good.

Yesterday while copying some files, suddenly I noticed that this feature is there now. Pretty useful feature to have. Here’s the screen-shot.

Make any command read line enabled (on *nix)

Make any command read line enabled (on *nix)

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      rlwrap sqlite3 database.db
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Enable readline even if the command line application is not using it.

* View this command to comment, vote or add to favourites * View all commands by pykler

commandlinefu.com

by David Winterbottom (codeinthehole.com)

URL: http://feedproxy.google.com/~r/Command-line-fu/~3/mKEgYoyHCMA/make-any-command-read-line-enabled-on-nix

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