Commands by rwilson04 (4)

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Rename files in batch

Remove a range of lines from a file
Delete a range of line

Always tail/edit/grep the latest file in a directory of timestamped files
zsh only If you have this command in your history, you can always re-run it and have it reference the latest file. The glob matches all timestamped files and then the resulting array is sorted by modification time (m) and then the first element in the sorted array is chosen (the latest)

Testing php configuration

Change a specific value in a path
Awk replaces the value of a specific field while retaining the field separator "/" .

Gets directory and files tree listing from a FTP-server
Creates a file with contents like `du -a`, only it is remote server filesystem hierarchy. Very usefull then for grep-ing without remote connection.

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

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" }

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"

Picture Renamer
jhead is a very nice tool to do all sorts of things with photographs, in a batch-oriented way. It has a specific function to rename files based on dates, and the format I used above was just an example.


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