Commands by 0x2142 (4)

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Join the content of a bash array with commas
$ DOCKER_APP_VARS=(DATABASE_USER=dbuserro, DATABASE_PASSWORD=maipass) [jeff@omniscience container] (master)$ echo docker run $(printf -- " -e %s" ${DOCKER_APP_VARS[*]}) -name 12factorapp mattdm/fedora-small docker run -e DATABASE_USER=dbuserro, -e DATABASE_PASSWORD=maipass -name 12factorapp mattdm/fedora-small Note that the printf method by itsself doesn't include a newline (\n), so you'll need to embed it into an echo statement or something that does.

Graphically show percent of mount space used
Automatically drops mount points that have non-numeric sizes (e.g. /proc). Tested in bash on Linux and AIX.

rsync with progress bar.
transfer files from localhost to a remotehost.

Efficiently extract lines between markers
GNU Sed can 'address' between two regex, but it continues parsing through to the end of the file. This slight alteration causes it to terminate reading the input file once the STOP match is made. In my example I have included an extra '/START/d' as my 'start' marker line contains the 'stop' string (I'm extracting data between 'resets' and using the time stamp as the 'start'). My previous coding using grep is slightly faster near the end of the file, but overall (extracting all the reset cycles in turn) the new SED method is quicker and a lot neater.

most used unix commands

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Optimal way of deleting huge numbers of files

Pipe a textfile to vim and move the cursor to a certain line
This command is more for demonstrating piping to vim and jumping to a specific line than anything else. Exit vim with :q! +23 jumps to line 23 - make vim receive the data from the pipe

Make directory including intermediate directories
This will create the intermediate directories that do not exist. I did not know about this for a long time.

quickly formats a fat partition. usefull for flash drives


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