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cat (concatenate) prints files to the terminal, one after another. ~/project has a few small files to work with.
This lab is the hands-on companion to the cat lesson from Linux Journey (CC BY-SA 4.0).
cat dogfile
Dogs bark.
Give cat several files and it prints them in order. > sends that output into a file instead of the screen:
cat dogfile birdfile > animals
cat animals
> replaces the file's contents; >> would add to the end.
With no file to read, cat reads what you type. Redirect it into a file:
cat > shopping.txt
Type a few lines (for example eggs and bread), pressing Enter after each. Then press Ctrl+D on an empty line to finish.
cat shopping.txt
-n numbers every line. -s squeezes runs of blank lines into one:
cat -n script.sh
cat -s messy.txt
cat file prints a file; cat a b prints both in order.> writes output to a file (replacing it) and >> appends.cat > file saves what you type until Ctrl+D.-n numbers lines and -s squeezes blank lines.