Commands by Cammander (1)

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Internet Speed Test
Make sure the file you use in your test is > 50mb to get good results. Dependancies: sudo apt-get install lftp iperf

Create a persistent connection to a machine
Create a persistent SSH connection to the host in the background. Combine this with settings in your ~/.ssh/config: Host host ControlPath ~/.ssh/master-%r@%h:%p ControlMaster no All the SSH connections to the machine will then go through the persisten SSH socket. This is very useful if you are using SSH to synchronize files (using rsync/sftp/cvs/svn) on a regular basis because it won't create a new socket each time to open an ssh connection.

Function to split a string into an array
It works as a method applicated to a variable, converts the string variable into an array

Short URL to commandlinefu.com commands
Obviously replace the relevant parts as required. The following also work: $ lynx cmdl.in/efu/by-marcel -or- $ lynx cmdl.in/efu/view-9058

list files recursively by size

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" }

Determine next available UID
better with accounts on ldap

copy remote ssh session output to local clipboard
ssh from local to remote and pipe output of file to the local clipboard

Backup a file with a date-time stamp
Appends the input file with the date format YYYY-MM-DD.bak. Also runs silently if you remove the -v on the cp at the end of the function.

Simultaneously running different Firefox profiles
After running $ firefox -ProfileManager and creating several different profiles, use this command to run multiple Firefox profiles simultaneously.


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