GETHOSTID(3) | Library Functions Manual | GETHOSTID(3)

# NAME

`gethostid`, `sethostid` — get/set unique identifier of current host

# SYNOPSIS

`#include <unistd.h>`

long
`gethostid`(void);

int
`sethostid`(long hostid);

# DESCRIPTION

The `sethostid`() function establishes a 32-bit identifier for the current processor that is intended to be unique among all UNIX systems in existence. This is normally an Internet address for the local machine. This call is allowed only to the superuser and is normally performed at boot-time.

`gethostid`() returns the 32-bit identifier for the current processor.

This function has been deprecated. The hostid should be set or retrieved by use of sysctl(2).

# SEE ALSO

sysctl(2), gethostname(3), sysctl(8)

# HISTORY

The `gethostid`() and `sethostid`() system calls first appeared in 4.1cBSD and were dropped in 4.4BSD.

# BUGS

32 bits for the identifier is too small.

March 3, 2019 | Debian