#include <unistd.h>int gethostname(char *name, int namelen);
The gethostname() function returns the standard host name for the current processor, as previously set by sethostname() . The namelen argument specifies the size of the array pointed to by name . The returned name is null-terminated unless insufficient space is provided.
The sethostname() function sets the name of the host machine to be name , which has length namelen . This call is restricted to the super-user and is normally used only when the system is bootstrapped.
Host names are limited to MAXHOSTNAMELEN characters, currently 256, defined in the <netdb.h> header.
Upon successful completion, gethostname() and sethostname() return 0 . Otherwise, they return -1 and set errno to indicate the error.
The gethostname() and sethostname() functions will fail if:
The name or namelen argument gave an invalid address.
The sethostname() function will fail if:
The caller was not the super-user.