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GZip all files in a directory separately
It gzip each file in a directory separately

Combine all .mpeg files in current directory into one big one.
Good old cat & output redirection. Using this method you can combine all kinds of things - even mpeg files. My video camera makes a series of .mpeg files that are broken into 4gb chunks. Using this command I can easily join them together. Even better, combined with the cp command the files can be copied and joined in one step.

Check if your desired password is already available in haveibeenpwnd database. This command uses the API provided by HIBP

Make vim open in tabs by default (save to .profile)
I always add this to my .profile rc so I can do things like: "vim *.c" and the files are opened in tabs.

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

Prevent overwriting file when using redirection
If you set noclobber to on, bash won't allow redirection to overwrite existing files . $ set -o noclobber command turn the option on (default it s off ) . You can still append information but not overwrite the file .to turn it back off use : $ set +o noclobber . I use it because i overwrite a file by accident , after thought , content of the file was very important , creating a one more file mean nothing for my hard disk (we are not anymore on the 64 k memory time) , but content of file is far much important . What we call exeprience :(

Compare a remote file with a local file
Useful for checking if there are differences between local and remote files.

Get duration of an audio file in seconds.
This is an alternative to #9131. ffmpeg didn't work on my .au files, though it did on the .wav ones. Also useful if you don't have ffmpeg but do have sox. Handily, sox already reports in seconds (decimal).

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.

SHA256 signature sum check of file
get the SHA256 sum signatur for a file


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