Commands by brettalton (5)

  • (relies on 'imagemagick') Convert all .png files to .gif. This can also go the other way if you reverse the file extensions in the command, e.g.: for file in *.gif; do convert "$file" "$(basename $file .gif).png"; done If the file is named 'example1.png' it will be named 'example1.gif' when it is complete.


    4
    for file in *.png; do convert "$file" "$(basename $file .png).gif"; done
    brettalton · 2009-02-15 23:39:08 15
  • (relies on 'imagemagick') This command will convert all .pdf files in a directory into a 800px (wide or height, whichever is smaller) image (with the aspect ratio kept) .jpg. If the file is named 'example1.pdf' it will be named 'example1.jpg' when it is complete. This is a VERY worthwhile command! People pay hundreds of dollars for this in the Windows world. My .jpg files average between 150kB to 300kB, but your's may differ. Show Sample Output


    29
    for file in `ls *.pdf`; do convert -verbose -colorspace RGB -resize 800 -interlace none -density 300 -quality 80 $file `echo $file | sed 's/\.pdf$/\.jpg/'`; done
    brettalton · 2009-02-15 23:27:43 20
  • .daa is a non-standard disk image format that can not be read by any other program. This is how you can extract the files though. PowerISO binary for Linux: http://www.poweriso.com/poweriso-1.3.tar.gz "This is a free utility for linux which can extract, list, and convert image files (including ISO, BIN, DAA, and other formats). Type " poweriso -? " for detailed usage information. File Size: 278KB"


    -2
    ./poweriso extract $USER/file.daa / -od $USER/file_extracted
    brettalton · 2009-02-15 23:19:40 9
  • In July 2008, there was an uproar over Foxconn motherboards feeding Linux installs incorrect ACPI information (http://ubuntu-virginia.ubuntuforums.org/showthread.php?t=869249). Foxconn has gladly corrected their mistake, but make sure it's not happening on your motherboard! After running the command, just view the 'dsdt.dsl' in any editor you like. Show Sample Output


    -1
    sudo aptitude -y install iasl && sudo cat /sys/firmware/acpi/tables/DSDT > dsdt.dat && iasl -d dsdt.dat
    brettalton · 2009-02-15 23:13:50 13
  • Use mencoder to concatenate (join) multiple video files together. Show Sample Output


    9
    mencoder -forceidx -ovc copy -oac copy -o output.avi video1.avi video2.avi
    brettalton · 2009-02-15 23:05:32 13

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Run a command only when load average is below a certain threshold
Good for one off jobs that you want to run at a quiet time. The default threshold is a load average of 0.8 but this can be set using atrun.

Convert spaces in file names to underscores

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"

Burn CD/DVD from an iso, eject disc when finished.
cdrecord -scanbus will tell you the (x,y,z) value of your cdr (for example, mine is 3,0,0)

Create a single PDF from multiple images with ImageMagick
Given some images (jpg or other supported formats) in input, you obtain a single PDF file with an image for every page.

batch convert Nikon RAW (nef) images to JPG
converts RAW files from a Nikon DSLR to jpg for easy viewing etc. requires ufraw package

Let's make screen and ssh-agent friends
When you start screen as `ssh-agent screen`, agent will die after detatch. If you don't want to take care about files when stored agent's pid/socket/etc, you have to use this command.

creeate file named after actual date
Create a file with actual date as filename

Which .service related this file?
I use this as an alias to get all .service files related a single installed file/conf (if it has services, of course). For rpm based systems ;)

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"


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