REV(1) User Commands REV(1)

# [NAME](#NAME)

rev - reverse lines characterwise

# [SYNOPSIS](#SYNOPSIS)

**rev** \[option] \[*file*...]

# [DESCRIPTION](#DESCRIPTION)

The **rev** utility copies the specified files to standard output, reversing the order of characters in every line. If no files are specified, standard input is read.

This utility is a line-oriented tool and it uses in-memory allocated buffer for a whole wide-char line. If the input file is huge and without line breaks then allocating the memory for the file may be unsuccessful.

# [OPTIONS](#OPTIONS)

**-0**, **--zero**

*Zero termination*. Use the byte '\\0' as line separator.

**-h**, **--help**

Display help text and exit.

**-V**, **--version**

Display version and exit.

# [SEE ALSO](#SEE_ALSO)

[**tac**(1)](/man/os/util-linux/tac.1)

# [REPORTING BUGS](#REPORTING_BUGS)

For bug reports, use the *issue tracker* <https://github.com/util-linux/util-linux/issues>.

# [AVAILABILITY](#AVAILABILITY)

The **rev** command is part of the util-linux package which can be downloaded from *Linux Kernel Archive* <https://www.kernel.org/pub/linux/utils/util-linux/>.

2026-09-25 util-linux 2.42.4

---

Document: rev(1) from util-linux 2.42.4-r0 (Chainguard OS)