---
name: "gethostuuid"
section: "2"
platform: "macos"
package: "Libc"
version: "1752.120.2"
release: "macOS 26.5"
platforms: ["macos"]
url: "https://new.carta.tech/gethostuuid"
---

# gethostuuid(2)

return a unique identifier for the current machine

## NAME

**gethostuuid** – return a unique identifier for the current machine

## SYNOPSIS

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

*int*\

**gethostuuid**(*uuid\_t id*, *const struct timespec \*wait*);

## DESCRIPTION

The **gethostuuid**() function returns a 16-byte *uuid\_t* specified by *id*, that uniquely identifies the current machine. Be aware that the hardware identifiers that **gethostuuid**() uses to generate the UUID can themselves be modified.

The *wait* argument is a pointer to a *struct timespec* that specifies the maximum time to wait for the result. Setting the *tv\_sec* and *tv\_nsec* fields to zero means to wait indefinitely until it completes.

## RETURN VALUES

The **gethostuuid**() function returns zero on success or -1 on error.

## ERRORS

The **gethostuuid**() functions fails if:

- \[EFAULT\]

  *wait* points to memory that is not a valid part of the process address space.

- \[EWOULDBLOCK\]

  The *wait* timeout expired before the UUID could be obtained.

## SEE ALSO

[uuid(3)](/uuid/3.md)