Commands by Crazor (0)

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Get ethX mac addresses
I much prefer using /sbin/ip over /sbin/ifconfig for most everything. I find the interface and output to be much more consistent and it has many abilities that ifconfig, route, etc. do not. To get the mac address for only one interface, add 'show dev [interface]' to the 'ip link' part of the command: ip link show dev eth0 | grep 'link/ether' | awk '{print $2}' . Also, both this command and the ifconfig one do not require root access to run, so the sudo is not necessary.

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" }

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)

Get video information with ffmpeg
I used an flv in my example, but it'll work on any file ffmpeg supports. It says it wants an output file, but it tells what you want to know without one.

Create and access directory at the same time
The previous alternative dont work (the cd command was missing).

Find file containing namespace in a directory of jar files.
You could subsitute javax.servlet for any namespace you need.

Take a file as input (two columns data format) and sum values on the 2nd column for all lines that have the same value in 1st column
Example: $ cat

Find the package that installed a command

File rotation without rename command
Rotates log files with "gz"-extension in a directory for 7 days and enumerates the number in file name. i.e.: logfile.1.gz > logfile.2.gz I needed this line due to the limitations on AIX Unix systems which do not ship with the rename command.

Get a free shell account on a community server
Bash process substitution which curls the website '' and executes the shell script embedded in the page. This is obviously not the most secure way to run something like this, and we will scold you if you try. The smarter way would be: Download locally over SSL > curl >> Verify integrty with GPG (If available) > gpg --recv-keys 0xD2C4C74D8FAA96F5 > gpg --verify Inspect source code > less Run > chmod +x > ./

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