Linux · Finding & Searching Files

which locates emacs instantly but returns nothing for a system command you know is installed. Why does an ordinary user hit this, and what resolves it?

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More in Finding & Searching Files

You need to locate a program's binary plus its man page and config files, not just the executable that PATH would run. Why does which fall short here, and what covers the wider set?

A colleague says locate is fast because it has an optimized filesystem-walk. What is actually the source of its speed, and what is the cost of that design?

On a modern system locate is provided by the plocate package rather than the classic tool. Where does plocate keep its database, and how do you control which directories get indexed?

When would you reach for find over locate even though find is much slower, and what does find return if you give it no search criteria?

In find, how do -mtime -5, -mtime +5, and -mtime 5 differ, and when would you switch to -ctime instead?

You want find to return only directories under /etc, and separately to list files owned by the users group that changed in the last five days. How do you express each, and what does -type d exclude?

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