Commands by brettalton (5)

  • Convert PNG to GIF

    (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 18
  • Convert PDF to JPG

    (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 25
  • Extract .daa files with PowerISO

    .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 10
  • View your motherboard's ACPI tables (in Debian & Ubuntu)

    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
  • Concatenate (join) video files

    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 15

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To create files with specific permission:

Clean all .pyc files from current project. It cleans all the files recursively.

Ping xxx.xxx.xxx.xxx ip 100000 times with size 1024bytes

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"

tar exclude files or directories
If you want to exclude only one file or directory you should use as --exclude=file_or_directory

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Benchmark SQL Query
Benchmark a SQL query against MySQL Server. The example runs the query 10 times, and you get the average runtime in the output. To ensure that the query does not get cached, use `RESET QUERY CACHE;` on top in the query file.

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

Check which files are opened by Firefox then sort by largest size.
Check which files are opened by Firefox then sort by largest size (in MB). You can see all files opened by just replacing grep to "/". Useful if you'd like to debug and check which extensions or files are taking too much memory resources in Firefox.

wget download with multiple simultaneous connections

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