Commands by theftf (1)

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Lookup errno defintions
Calls the POSIX strerror() function to look up the meaning of integer ERRNOs set by some functions.

dd with progress bar and statistics to gzipped image
This is a useful command to backup an sd card with relative total size for piping to pv with a progressbar

Convert a date to timestamp
Simple way to get a timestamp from a date

For finding out if something is listening on a port and if so what the daemon is.

Create subdirectory and move files into it
With this form you dont need to cut out target directory using grep/sed/etc.

Add a line to a file using sudo
This is the solution to the common mistake made by sudo newbies, since $ sudo echo "foo bar" >> /path/to/some/file does NOT add to the file as root. Alternatively, $ sudo echo "foo bar" > /path/to/some/file should be replaced by $ echo "foo bar" | sudo tee /path/to/some/file And you can add a >/dev/null in the end if you're not interested in the tee stdout : $ echo "foo bar" | sudo tee -a /path/to/some/file >/dev/null

Fast tape rewind
Traditionally we rewind a tape using this syntaxis: $ mt -f /dev/rmt/0cbn rewind Redirecting the dispositive to nothing as shown above is faster. Less typing is always better.

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" }

disable history for current shell session


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