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Search commandlinefu.com from the command line using the API
Search for one/many words on commandlinefu, results in vim for easy copy, manipulation. The -R flag is for readonly mode...you can still write to a file, but vim won't prompt for save on quit. What I'd really like is a way to do this from within vim in a new tab. Something like $ :Tex path/to/file but $ :cmdfu search terms

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

Check how far along (in %) your program is in a file
Imagine you've started a long-running process that involves piping data, but you forgot to add the progress-bar option to a command. e.g. $ xz -dc bigdata.xz | complicated-processing-program > summary . This command uses lsof to see how much data xz has read from the file. $ lsof -o0 -o -Fo FILENAME Display offsets (-o), in decimal (-o0), in parseable form (-Fo) This will output something like: . p12607 f3 o0t45187072 . Process id (p), File Descriptor (f), Offset (o) . We stat the file to get its size $ stat -c %s FILENAME . Then we plug the values into awk. Split the line at the letter t: -Ft Define a variable for the file's size: -s=$(stat...) Only work on the offset line: /^o/ . Note this command was tested using the Linux version of lsof. Because it uses lsof's batch option (-F) it may be portable. . Thanks to @unhammer for the brilliant idea.

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.

Convert Youtube videos to MP3
youtube-dl has this functionality built in. If you're running an older version of youtube-dl, you can update it using `youtube-dl -U` (although if you have an older version, it probably doesn't download youtube videos anyway.) youtube-dl --help will show you other options that may come in useful.

Unzip multiple files with one command
With this command you can easily unzip multiple zip files with just one command. All you need to do is to use single quotes.

Embed next line on the end of current line using sed
N: On the current line, sed will display it on pattern space, plus a \n (new line); but s/\n//: Will get rid of new line displayed on pattern space, joining the current line's end with the start of the next line Useful in scripts.

find packages installed from e.g. sid which are newer than those available from e.g. testing when sid is no longer present as a source repo
This is useful if you add sid, install some packages, then remove sid and want to work out which packages you installed from sid that should be removed (e.g. before an upgrade to the new stable). Alternatively you can think of this as "find installed packages that can no longer be installed."

get the full description of a randomly selected package from the list of installed packages on a debian system
I put this command on my ~/.bashrc in order to learn something new about installed packages on my Debian/Ubuntu system each time I open a new terminal


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