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In this lesson, I'd like to
tell you about width and locate.

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Not the most important utilities, but very convenient. That's
why I like to tell you about them. Anyway.

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So Find is very powerful and it's a thorough utility that
helps you find any file no matter where it is stored.

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The disadvantage of Find is that on
big file systems it might be slow,

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particularly if you have a composed
file system that integrates many other devices.

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And that's why you
might be interested in locate.

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Locate is much faster, but it works on a
database that needs to be defined using the updatedb command.

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And also you need
to update this database periodically.

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So if you are going to use locate and
if you want to rely on it, probably you want

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to use updatedb as scheduled job using cron or
systemd timers as explained later, which is also convenient. It

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is useful to find the exact location of binary
files from the path variable. Let me show you.

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So let me type LS and
let me use locate a file and

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then what do we get? We
get oh boy, locate. No such file

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or directory. And that's because updatedb
apparently has never happened on this system.

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So I need sudo
updatedb to generate it.

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And now I'm using locate
file and there you can see

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that it locates files that
match the text pattern file.

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So do realize that locate is
not going to need any wildcards and

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so on. It's just looking for
files that contain the text pattern.

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Now, how
about which.

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Which passwd, for instance, is printing the
name of usr bin passwd that makes that

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you can use constructions like LS l
and whichpass wd. Now what is that? When

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you put a command between a dollar
and parenthesis, that's what we call command substitution.

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And the result is that the command will work on
the result of the whichpass WD command. So you don't

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need to know where exactly this command is on your
valve system, which will find it out automatically for you.

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As I told you, small
utilities, but they can be convenient.