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play audio stream and video stream in two different mplayer instances
Sometimes audio and video are not sync'ed. The factor 1.0884 is the quotient 48000/44100. One mplayer plays the audio file in the background, the other the video in the foreground. You can dump the audio file before with another commandlinefu

Find the biggest files
Show the top 10 file size

create disk copy over the net without temp files
I wanted to create a copy of my whole laptop disk on an lvm disk of the same size. First I created the logical volume: lvcreate -L120G -nlaptop mylvms SOURCE: dd if=/dev/sda bs=16065b | netcat ip-target 1234 TARGET: nc -l -p 1234 | dd of=/dev/mapper/mylvms-laptop bs=16065b to follow its process you issue the following command in a different terminal STATS: on target in a different terminal: watch -n60 -- kill -USR1 $(pgrep dd) (see http://www.commandlinefu.com/commands/view/4356/output-stats-from-a-running-dd-command-to-see-its-progress)

Plaintext credentials sniffing with tcpdump and grep
Simple TCPDUMP grepping for common unsafe protocols (HTTP, POP3, SMTP, FTP)

list block devices
Shows all block devices in a tree with descruptions of what they are.

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

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" }

Periodic Display of Fan Speed with Change Highlights
Uses the lm-sensors package in Linux to display fan speed. Grep RPM is used to discover lines containing the text RPM, and sed is used to edit out everything but the RPM number. The watch utility is used to update the display every 10 seconds and -d highlights any changes from the previous value. The eval function of Bash is used to execute the command enclosed in the ".." string.

intercept stdout/stderr of another process
similar to the previous command, but with more friendly output (tested on linux)

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


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