Linux · Bash: Variables, Expansion & Globbing

You want the double-star pattern to find PDFs recursively through the current directory and every subdirectory, but it just behaves like an ordinary single star — what's missing?

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More in Bash: Variables, Expansion & Globbing

Before running a destructive command like rm on a glob, how can you preview exactly which files the pattern will hit?

By default echo * omits hidden files — how do you make globbing include dotfiles, and how do you turn it back off?

Why does find ... | ls -l show the current directory instead of find's results, and what two mechanisms actually pass find's output to ls?

When feeding a very large list of files to a command, why can xargs succeed where $(command) substitution fails?

Piping filenames through find | xargs breaks when a filename contains a space — what pair of options makes it robust?

A beginner writes var = abc to set a variable and it fails — what is the exact syntax rule being violated?

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