---
name: "cat"
section: "1"
platform: "freebsd"
package: "base"
version: "16.0-CURRENT-20261027-61c70dc16a79"
release: "FreeBSD 16.0-CURRENT (2026-10-27)"
platforms: ["linux", "freebsd", "openbsd", "macos"]
url: "https://new.carta.tech/cat"
---

# cat(1)

concatenate and print files

## NAME

**cat** – concatenate and print files

## SYNOPSIS

**cat** \[**-AbeElnstTuv**\] \[*file ...*\]

## DESCRIPTION

The **cat** utility reads files sequentially, writing them to the standard output. The *file* operands are processed in command-line order. If *file* is a single dash (‘**-**’) or absent, **cat** reads from the standard input. If *file* is a UNIX domain socket, **cat** connects to it and then reads it until EOF. This complements the UNIX domain binding capability available in [inetd(8)](/inetd/8.md).

The options are as follows:

- **-A**

  Equivalent to specifying the **-v** , **-E** and **-T** options.

- **-b**

  Number the non-blank output lines, starting at 1.

- **-e**

  Equivalent to specifying the **-E** and **-v** options.

- **-E**

  Display a dollar sign (‘$’) at the end of each line.

- **-l**

  Set an exclusive advisory lock on the standard output file descriptor. This lock is set using [fcntl(2)](/fcntl/2.md) with the F\_SETLKW command. If the output file is already locked, **cat** will block until the lock is acquired.

- **-n**

  Number the output lines, starting at 1.

- **-s**

  Squeeze multiple adjacent empty lines, causing the output to be single spaced.

- **-T**

  Display tab characters as ‘^I’.

- **-t**

  Equivalent to specifying the **-T** and **-v** options.

- **-u**

  Disable output buffering.

- **-v**

  Display non-printing characters so they are visible. Control characters print as ‘^X’ for control-X; the delete character (octal 0177) prints as ‘^?’. Non-ASCII characters (with the high bit set) are printed as ‘M-’ (for meta) followed by the character for the low 7 bits.

## EXIT STATUS

The **cat** utility exits 0 on success, and \>0 if an error occurs.

## EXAMPLES

The command:

```
cat file1
```

will print the contents of *file1* to the standard output.

The command:

```
cat file1 file2 > file3
```

will sequentially print the contents of *file1* and *file2* to the file *file3*, truncating *file3* if it already exists. See the manual page for your shell (e.g., [sh(1)](/sh/1.md)) for more information on redirection.

The command:

```
cat file1 - file2 - file3
```

will print the contents of *file1*, print data it receives from the standard input until it receives an EOF (‘^D’) character, print the contents of *file2*, read and output contents of the standard input again, then finally output the contents of *file3*. Note that if the standard input refers to a file, the second dash on the command-line would have no effect, since the entire contents of the file would have already been read and printed by **cat** when it encountered the first ‘**-**’ operand.

## SEE ALSO

[head(1)](/head/1.md), [more(1)](/more/1.md), [pr(1)](/pr/1.md), [sh(1)](/sh/1.md), [tail(1)](/tail/1.md), [vis(1)](/vis/1.md), [zcat(1)](/zcat/1.md), [fcntl(2)](/fcntl/2.md), [setbuf(3)](/setbuf/3.md) Rob Pike, “UNIX Style, or cat -v Considered Harmful”, *USENIX Summer Conference Proceedings*, 1983.

## STANDARDS

The **cat** utility is compliant with the IEEE Std 1003.2-1992 (“POSIX.2”) specification.

The flags \[**-AbeElnstTv**\] are extensions to the specification.

## HISTORY

A **cat** utility appeared in Version 1 AT&T UNIX. Dennis Ritchie designed and wrote the first man page. It appears to have been for **cat**.

## BUGS

Because of the shell language mechanism used to perform output redirection, the command “cat file1 file2 \> file1” will cause the original data in *file1* to be destroyed!

The **cat** utility does not recognize multibyte characters when the **-t** or **-v** option is in effect.