Commands by algol (3)

  • Creates a PDF file where each page will be a layer from de original TIFF file. You can apply many other filters and transformations. convert multi_layer.tif -page a4 -compress jpg multi_page.pdf To set the page size convert multi_layer.tif -crop 590x790+20+30 -compress jpg multi_page.pdf To include only a portion of the image (discard first horizontal 20 pixels and first vertical 30 pixels, include the next 590 horizontal and 790 vertical pixels) convert multi_layer.tif -delete 1,3,5-10 -compress jpg multi_page.pdf Discard mentioned layers


    0
    convert multi_layer.tif -compress jpg multi_page.pdf
    algol · 2013-09-26 14:44:01 12
  • Open all files which have some string go directly to the first line where that string is and run command on it. Other examples: Run vim only once with multiple files (and just go to string in the first one): grep -rl string_to_find public_html/css/ | xargs vim +/string_to_find Run vim for each file, go to string in every one and run command (to delete line): grep -rl string_to_find public_html/css/ | xargs -I '{}' vim +/string_to_find {} -c ":delete"


    -1
    grep -rl string_to_find public_html/css/ | xargs -I '{}' vim +/string_to_find {} -c ":s/string_to_find/string_replaced"
    algol · 2012-11-07 14:44:51 6
  • I like to label my grub boot options with the correct kernel version/build. After building and installing a new kernel with "make install" I had to edit my grub.conf by hand. To avoid this, I've decided to write this little command line to: 1. read the version/build part of the filename to which the kernel symlinks point 2. replace the first label lines of grub.conf grub.conf label lines must be in this format: Latest [{name}-{version/build}] Old [{name}-{version/build}] only the {version/build} part is substituted. For instance: title Latest [GNU/Linux-2.6.31-gentoo-r10.201003] would turn to title Latest [GNU/Linux-2.6.32-gentoo-r7.201004]"


    1
    LATEST=`readlink /boot/vmlinuz`; OLD=`readlink /boot/vmlinuz.old`; cat /boot/grub/grub.conf | sed -i -e 's/\(Latest \[[^-]*\).*\]/\1-'"${LATEST#*-}"]'/1' -e 's/\(Old \[[^-]*\).*\]/\1-'"${OLD#*-}"]'/1' /boot/grub/grub.conf
    algol · 2010-04-21 19:16:51 8

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands


Check These Out

Tell local Debian machine to install packages used by remote Debian machine
(also works on Ubuntu) Copies the 'install,' 'hold,' 'deinstall' and 'purge' states of packages on the remote machine to be matched on the local machine. Note: if packages were installed on the local machine that were never installed on the remote machine, they will not be deinstalled by this operation.

Clear the terminal screen
works in /bin/bash

Find the package that installed a command

list files recursively by size

Blue Matrix
Same as original, but works in bash

True Random Dice Roll

Produce a pseudo random password with given length in base 64
Of course you will have to install Digest::SHA and perl before this will work :) Maximum length is 43 for SHA256. If you need more, use SHA512 or the hexadecimal form: sha256_hex()

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

list ips with high number of connections


Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: