Commands by jimthunderbird (11)

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RTFM function
Same as the other rtfm's, but using the more correct xdg-open instead of $BROWSER. I can't find a way to open info only if the term exists, so it stays out of my version.

Generate Sha1, MD5 hash using echo
This is mostly for my own notes but this command will compute a md5 message digest from the command line. You can also replace md5sum with other checksum commands (e.g., sha1sum)

cd to (or operate on) a file across parallel directories
This is useful for quickly jumping around branches in a file system, or operating on a parellel file. This is tested in bash. cd to (substitute in PWD, a for b) where PWD is the bash environmental variable for the "working directory"

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" }

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Bind a key with a command
the -x option is for binding to a shell command

make directory with current date

Print a date from 3 days ago
This command prints the Date (Not time) from 3 days ago (72 hours ago). This works on systems without GNU date (MacOSX , Solaris, FreeBSD).

pretend to be busy in office to enjoy a cup of coffee
Dialog's gauge widget accepts progress updates on stdin. This version runs dialog once and updates it every second. There's no need to use timeout which causes screen flicker since it restarts dialog for each update.

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"


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