---
name: "uuid_unparse"
section: "3"
platform: "linux"
package: "util-linux-libs"
version: "2.42.4-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/uuid_unparse"
---

# uuid\_unparse(3)

convert a UUID from binary representation to a string

## NAME

uuid\_unparse - convert a UUID from binary representation to a string

## SYNOPSIS

**#include \<uuid.h\>**

**void uuid\_unparse(const uuid\_t** *uu***, char \****out***);**\
 **void uuid\_unparse\_upper(const uuid\_t** *uu***, char \****out***);**\
 **void uuid\_unparse\_lower(const uuid\_t** *uu***, char \****out***);**

## DESCRIPTION

*The* **uuid\_unparse***() function converts the supplied UUID uu from the binary representation into a 36-byte string (plus trailing '\\0') of the form 1b4e28ba-2fa1-11d2-883f-0016d3cca427 and stores this value in the character string pointed to by out. The case of the hex digits returned by* **uuid\_unparse***() may be upper or lower case, and is dependent on the system-dependent local default.*

*If the case of the hex digits is important then the functions* **uuid\_unparse\_upper***() and* **uuid\_unparse\_lower***() may be used.*

## CONFORMING TO

*This library unparses UUIDs compatible with OSF DCE 1.1.*

## AUTHORS

*Theodore Y. Ts’o*

## SEE ALSO

**uuid***(3),* **uuid\_clear***(3),* **uuid\_compare***(3),* **uuid\_copy***(3),* **uuid\_generate***(3),* **uuid\_time***(3),* **uuid\_is\_null***(3),* **uuid\_parse***(3)*

## REPORTING BUGS

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

## AVAILABILITY

*The* **libuuid** *library is part of the util-linux package since version 2.15.1. It can be downloaded from* *Linux Kernel Archive \<https://www.kernel.org/pub/linux/utils/util-linux/\>.*