cut (extract columns) in Linux CLI - Step-by-Step Execution

Concept Flow - cut (extract columns)

Input text or file

↓

Specify delimiter or default tab

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Specify fields or character positions

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cut extracts specified columns

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Output extracted columns

The cut command reads input, uses a delimiter to split columns, extracts specified columns, and outputs them.

Execution Sample

Linux CLI

echo "apple,banana,cherry" | cut -d',' -f2

Extracts the second column (banana) from a comma-separated string.

Execution Table

Step	Input	Delimiter	Fields	Action	Output
1	"apple,banana,cherry"	','	2	Split input by ','	["apple", "banana", "cherry"]
2	["apple", "banana", "cherry"]	','	2	Extract field 2	"banana"
3	"banana"	N/A	N/A	Print output	banana

💡 All specified fields extracted and printed; command ends.

Variable Tracker

Variable	Start	After Step 1	After Step 2	Final
input_line	"apple,banana,cherry"	"apple,banana,cherry"	"apple,banana,cherry"	"apple,banana,cherry"
delimiter	tab (default)	','	','	','
fields	none	2	2	2
split_fields	none	["apple", "banana", "cherry"]	["apple", "banana", "cherry"]	["apple", "banana", "cherry"]
output	none	none	"banana"	"banana"

Key Moments - 3 Insights

Why does cut use a delimiter and what happens if I don't specify one?

cut uses the delimiter to know where to split the input into columns. If you don't specify one, it uses the tab character by default (see execution_table step 1).

What does the -f2 option mean in the cut command?

-f2 tells cut to extract the second field (column) after splitting by the delimiter, as shown in execution_table step 2.

Can cut extract multiple columns at once?

Yes, you can specify multiple fields like -f1,3 to extract first and third columns. This example shows a single field for simplicity.

Visual Quiz - 3 Questions

Look at the execution_table, what is the output after step 2?

A "banana"

B "apple"

C "cherry"

D "apple,banana,cherry"

💡 Hint

Check the 'Output' column in execution_table row for step 2.

At which step does cut split the input string into fields?

A Step 2

B Step 1

C Step 3

D No splitting occurs

💡 Hint

Look at the 'Action' column in execution_table to find when splitting happens.

If the delimiter was not specified, what delimiter would cut use by default?

A Comma ','

B Space ' '

C Tab '\t'

D Semicolon ';'

💡 Hint

Check variable_tracker for the initial delimiter value.

Concept Snapshot

cut command extracts columns from text.
Use -d to set delimiter (default is tab).
Use -f to specify which columns to extract.
Example: cut -d',' -f2 extracts second column from comma-separated input.
Outputs only the selected columns.

Full Transcript

The cut command takes input text or a file and splits it into columns using a delimiter. By default, the delimiter is a tab character. You specify which columns to extract using the -f option. For example, echo "apple,banana,cherry" | cut -d',' -f2 splits the input by commas and extracts the second column, which is "banana". The command outputs only the selected columns. This process involves reading the input, splitting it by the delimiter, extracting the requested fields, and printing them. If no delimiter is specified, cut assumes tab. You can extract multiple columns by listing them with commas in the -f option.