Master Linux File Management Commands: cat, cmp, diff, file, find

File Management Commands

cat

The cat command concatenates files and prints their contents to standard output. cat [options] [filename] Key parameters are illustrated below:

Examples:

for i in $(seq 1 10); do echo $i >> test1.txt; done

cat test1.txt

cat -n test1.txt > test2.txt

cat test2.txt

cat /dev/null > test1.txt

cmp

The cmp command compares two files byte by byte and reports the first difference.

cmp [-clsv] [-i <count>] [first_file] [second_file]

Parameters are shown in the following image:

Examples:

for i in $(seq 1 5); do echo $i >> test1.txt; done

cmp test1.txt test2.txt

diff

The diff command compares files line by line and shows differences; it can also compare directories. diff [options] file1 file2 Parameters are illustrated below:

Example (side‑by‑side output):

diff test1.txt test2.txt -y -W 50

file

The file command determines the type of a file. file [options] [filename] Parameters are shown in the image:

Examples:

file test1.txt

file -b test2.txt

find

The find command searches for files and directories matching given criteria. find [options] [path] [expression] Key parameters are illustrated below:

Examples:

find . -name "*.txt"

find / -type f -size 0 -exec ls -l {} \;