Commands by pdxdoughnut (30)

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Perform a branching conditional
This will perform one of two blocks of code, depending on the condition of the first. Essentially is a bash terniary operator. To tell if a machine is up: $ ping -c1 machine { echo succes;} || { echo failed; } Because of the bash { } block operators, you can have multiple commands $ ping -c1 machine && { echo success;log-timestamp.sh }|| { echo failed; email-admin.sh; } Tips: Remember, the { } operators are treated by bash as a reserved word: as such, they need a space on either side. If you have a command that can fail at the end of the true block, consider ending said block with 'false' to prevent accidental execution

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"

Put a console clock in top right corner
Gives not only date but also some interesting status about the System

Who needs pipes?
or: C

List all information about all files (in current dir)
This is a funny usage of the traditional command ls. It could be basically simplified as: $ ls -a -l Duplicating arguments is permitted: $ ls -a -l -l And this markup could be shortened as: $ ls -al Extra note: To view filesizes like a pro, pray for your God: $ ls -allah

Insert a line at the top of a text file without sed or awk or bash loops
Yet another way to add a line at the top a of text file with the help of the tac command (reverse cat).

Mount SMB share with password containing special characters
If the password for the share your trying to mount contains special characters you can use URL escape characters. The above command uses an example as follows: username: user password: p@ss URL Encoded password: p%40ss All credit goes to Richard York: http://www.smilingsouls.net/Blog/20110526100731.html Also check out this URL Decoder/Encoder to convert your passwords. http://meyerweb.com/eric/tools/dencoder/

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" }

Find the package that installed a command

Find top 5 big files
zsh: list of files sorted by size, greater than 100mb, head the top 5. '**/*' is recursive, and the glob qualifiers provide '.' = regular file, 'L' size, which is followed by 'm' = 'megabyte', and finally '+100' = a value of 100


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