GETHOSTID(3) NetBSD Library Functions Manual GETHOSTID(3)
gethostid, sethostid -- get/set unique identifier of current host
Standard C Library (libc, -lc)
#include <unistd.h> long gethostid(void); int sethostid(long hostid);
sethostid() 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 super-user 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(3).
gethostname(3), sysctl(3), sysctl(8)
The gethostid() and sethostid() syscalls appeared in 4.2BSD and were dropped in 4.4BSD.
32 bits for the identifier is too small. NetBSD 9.0 March 3, 2019 NetBSD 9.0
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