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- In this video, we will talk about cut

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and sort, which are easy to use
text manipulation utilities.

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To start with, there is cut,

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which you would use to filter
out columns from text files.

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If you want to use it the right way,

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you do need to specify to
the field the delimiter.

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In cut, that is -d.

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This -d is what you are going to use

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to specify how cut can recognize fields,

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and let's just have a
look at two examples.

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The first example is
cut -f 3, etc, passwd,

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then we have cut -d :-f 3, etc, passwd.

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Let me show you.

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So let's start with cut
-f 3 on etc, passwd,

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and what do we see?

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Well, we don't see any fields at all.

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It just prints the entire contents.

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Why is that?

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That is because it has no
idea how to recognize a field,

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and that is why we need to add
the field's delimiter, - d :.

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The colon is the field delimiter
in this configuration file,

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and if you specify -d :, then there we go.

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We print the third field from etc, passwd.

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Often used together
with cut, there is sort.

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Sort will sort the result
of the cut command.

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By default, it will do
that in alphabetical order.

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If you don't want it, you can use -n.

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- n will sort in numeric order.

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Let's just compare the
behavior of these two commands.

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First command is where
we are using just sort.

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Second command, where we are sorting -n.

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So here, back to our previous command.

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First, if you pipe through
sorts, then what do we see?

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Well, we see that this
is how it is sorting.

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So first, all the items
that start with a one,

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then all the items that start with a two.

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That's probably not what you want,

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and that is why you
wanna do a numeric sort.

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So sort -n is sorting in a numeric way.