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 0
  • 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 1
  • 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 0

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