Commands by smcpherson (6)

  • Copy files over network using compression

    This is useful for sending data between 2 computers that you have shell access to. Uses tar compression during transfer. Files are compressed & uncompressed automatically. Note the trailing dash on the listening side that makes netcat listen to stdin for data. on the listening side: sudo nc -lp 2022 | sudo tar -xvf - explanation: open netcat to -l listen on -p port 2022, take the data stream and pipe to tar -x extract, -v verbose, -f using file filename - means "stdin" on the sending side: tar -cvzf - ./*| nc -w 3 name_of_listening_host 2022 explanation: compress all files in current dir using tar -c create, -v verbose, -f using file, - filename - here means "stdout" because we're tar -c instead of tar -x, -w3 wait 3 seconds on stream termination and then end the connection to the listening host name_of_listening_host, on port 2022


    -2
    on the listening side: sudo nc -lp 2022 | sudo tar -xvf - and on the sending side: tar -cvzf - ./*| nc -w 3 name_of_listening_host 2022
    smcpherson · 2009-03-27 09:59:33 7
  • Combine all .mpeg files in current directory into one big one.

    Good old cat & output redirection. Using this method you can combine all kinds of things - even mpeg files. My video camera makes a series of .mpeg files that are broken into 4gb chunks. Using this command I can easily join them together. Even better, combined with the cp command the files can be copied and joined in one step.


    2
    cat *.mpg > all.mpg
    smcpherson · 2009-03-27 04:49:18 4
  • Move all files with common extension to current directory

    This is useful if you have a collection of files in folders (for example, a bunch of .zip files that are contained in folders) and you want to move them all to a common folder.


    -8
    mv `find .zip ./` .
    smcpherson · 2009-03-27 04:42:48 5
  • convert a .mp4 to a .avi


    0
    ffmpeg -i "/path/to/file.mp4" "/path/to/file.avi"
    smcpherson · 2009-03-27 04:36:41 2
  • convert a .wmv to a .avi


    1
    mencoder "/path/to/file.wmv" -ofps 23.976 -ovc lavc -oac copy -o "/path/to/file.avi"
    smcpherson · 2009-03-27 04:35:08 3
  • Display condensed log of changes to current git repository

    Assuming you are working within a git repository, you can run the above command & see what has changed in reverse chronological order, with one commit per line. Other formatting variations to 'oneline' include 'short', 'medium', 'full', 'fuller', 'email' or 'raw'. Show Sample Output


    2
    git log --pretty=oneline
    smcpherson · 2009-03-27 04:16:43 0

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list files recursively by size

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

Open the last file you edited in Vim.

Create a single-use TCP proxy with debug output to stderr
or you can add "-x" to get a typical hexdump like output

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" }

To get internet connection information .
To get the connection information of protocol tcp and extended infortmation.

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"

Empty a file

Create a backdoor on a machine to allow remote connection to bash
My netcat (nc-1.84-10.fc6) doesn't have the -e option, so I have to do it like this. Of course, instead of bash, you can use any executable, including scripts.

diff the outputs of two programs
I've been looking for this for a long time. Does anybody know how to do this in dash (POSIX shell)? An alternative version might be: $ exiftool img_1.jpg | diff -

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