Commands tagged GNU Preprocessor (1)

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Play online music videos in terminal
pvl 'link1' 'link2' 'link3' Play Youtube, Vimeo, etc links without visual elements. Great for music videos when you just want the audio. You can control mplayer with this! Hit Ctrl-C twice to exit (if you're playing multiple files)

The Chronic: run a command every N seconds in the background
Chronic Bash function: $ chronic 3600 time # Print the time in your shell every hour $ chronic 60 updatedb > /dev/null # update slocate every minute Note: use 'jobs' to list background tasks and fg/bg to take control of them.

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"

identify exported sonames in a path
This provides a list of shared object names (sonames) that are exported by a given tree. This is usually useful to make sure that a given required dependency (NEEDED entry) is present in a firmware image tree. The shorter (usable) version for it would be $ scanelf -RBSq -F "+S#f" But I used the verbose parameters in the command above, for explanation.

List the size (in human readable form) of all sub folders from the current location

Alert visually until any key is pressed
I learned a few things reading this command. But I did run into a few issues: 1. On systems that don't use GNU echo (e.g. macOS 10.14.5 Mojave), the e option may not be supported. In this case ANSI escape codes will echoed as text and the terminal will not flash, like this: \e[?5h\e[38;5;1m A L E R T Thu Jun 20 16:31:29 PDT 2019 2. Since the read command strips\ignores leading backslashes, if a user types the backslash character once in the loop, it will not break. Typing backslash twice in a loop will break as expected. 3. The foreground color is set to red (\e[38;5;1m) on every loop. This could be set once before we call while, and then reset once when the loop breaks. 4. Instead of resetting the foreground color when it breaks, the video mode is set back to normal (\e[?5l). This has the effect of leaving the terminal text red until it is manually reset. The alternative I'm proposing here addresses these issues. I tested it on macOS and Arch Linux.

Unix time to local time

download all the presentations from UTOSC2010
miss a class at UTOSC2010? need a refresher? use this to curl down all the presentations from the UTOSC website. ( NOTE/WARNING this will dump them in the current directory and there are around 37 and some are big - tested on OSX10.6.1

Insert a line at the top of a text file without sed or awk or bash loops
Just use '-' to use STDIN as an additional input to 'cat'

prevent accidents while using wildcards
alternative for "echo rm *.txt". Just doubletab the command you are willing to use and it will show you the affected files.

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