Commands by ironmarc (6)

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A function to find the newest file in a directory

Show the key code for keyboard events include the Fn keys
The keycodes are a result of pressing: Mute (Fn+F1) a

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" }

Recurse through directories easily
This is a simple case of recursing through all directories, adding the '.bak' extension to every file. Of course, the 'cp $file $file.bak' could be any code you need to apply to your recursion, including tests, other functions, creating variables, doing math, etc. Simple and clean recursion.

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Set a Reminder for yourself via the notification system
This will be seen through your system's visual notification system, notify-osd, notification-daemon, etc. --- sleep accepts s,m,h,d and floats (date; sleep .25m; date) --- notify-send (-t is in milliseconds && -u low / normal / critical) man notify-send for more information --- notification-daemon can use b/i/u/a HTML

Find files and list them sorted by modification time
Works with files containing spaces and for very large directories.

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

How to run X without any graphics hardware
This starts an X server using Xvfb(1) (no graphics hardware required), then starts a VNC server on the display. Change :1 if there's a conflict with an existing display, and change 800x600x24 to suit your tastes (24 is the bit depth, 800x600 is the size). This command obviously requires X be installed, and also x11vnc(1); both are available via your favourite package manager. You can also use another VNC server of your choosing, as long as DISPLAY is set to the display of Xvfb(1). To change your desktop environment (the default is twm(1), which is rather fail), you can add it to your ~/.xinitrc file (see the startx(1) manpage for details).

print contents of file from line 1 until we match regex
Start printing the contents of filename to stdout, until a matching line to regex is found, then stop.


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