GETHOSTNAME(3) NetBSD Library Functions Manual GETHOSTNAME(3)
gethostname, sethostname -- get/set name of current host
Standard C Library (libc, -lc)
#include <unistd.h> int gethostname(char *name, size_t namelen); int sethostname(const char *name, size_t namelen);
gethostname() returns the standard host name for the current machine, as previously set by sethostname(). The parameter namelen specifies the size of the name array. The returned name is null-terminated unless insufficient space is provided. sethostname() sets the name of the host machine to be name, which has length namelen. This call is restricted to the super-user and is nor- mally used only when the system is bootstrapped.
If the call succeeds a value of 0 is returned. If the call fails, a value of -1 is returned and an error code is placed in the global loca- tion errno.
If the gethostname() or sethostname() functions fail, they will set errno for any of the errors specified for the routine sysctl(3).
gethostid(3), sysctl(3), sysctl(8)
The gethostname() function conforms to X/Open Portability Guide Issue 4, Version 2 (``XPG4.2'').
The gethostname function call appeared in 4.2BSD.
Host names are limited to MAXHOSTNAMELEN (from <sys/param.h>) characters including null-termination, currently 256. NetBSD 8.1 September 2, 2015 NetBSD 8.1
You can also request any man page by name and (optionally) by section: