Name
cat [man page] – concatenate files and print on the standard output
Synopsis
cat [OPTION] [FILE]...
Frequently used options
-n, --number number all output lines
Examples
cat read content of a file(s) and print then on standard output which is in many cases our terminal. Lets suppose that our file samba.txt contain text:
Samba file and printer sharing is supported by all Linux Distributions: Suse Linux, Debian Linux,
Mandrake Linux, Red Hat Linux, Fedora Linux, Gentoo Linux
When we cat file cat.txt cat will read content of a file a spit it out to stdout:
cat samba.txt
As a description of this command suggest we can also concatenate two files. Our second file ubuntu.txt contain:
and Ubuntu Linux.
Lets see what happens when we cat both files at once:
$ cat samba.txt ubuntu.txt
Now we can use cat to concatenate two files and create new file samba_support.txt.
$ cat samba.txt ubuntu.txt > samba_support.txt
With use of pipe we can redirect output of cat command to another command such us bc:
$ echo '2+2' > '2+2.txt' $ cat 2+2.txt | bc
by -n option we also tell cat to number lines:
$ cat -n samba_support.txt