gethostname

gethostname

Gets the Host Name

Portability: UNIX compatible

SYNOPSIS
DESCRIPTION
RETURN VALUE
PORTABILITY
IMPLEMENTATION
PORTABILITY
EXAMPLE
RELATED FUNCTIONS

SYNOPSIS

int gethostname(char *name, int namelen);

DESCRIPTION

gethostname returns the host name for the current processor. namelen is the size of the name array. The returned host name is null-terminated unless there is not enough space in namelen .

RETURN VALUE

If gethostname succeeds, it returns a 0 . Otherwise, it returns a -1 , and sets errno to indicate the type of error.

PORTABILITY

gethostname is portable to other environments, including most UNIX systems, that implement BSD sockets. These other socket library implementations do not require the inclusion of the <netdb.h> header file. The SAS/C <netdb.h> header file contains #pragma map statements to create unique eight-character identifiers for the OS/390 and CMS linking utilities.

IMPLEMENTATION

The value that gethostname returns is assigned by the local host's TCP/IP software, which must be running in order for gethostid to succeed.

PORTABILITY

gethostname is portable to other environments, including most UNIX systems, that implement BSD sockets. To reduce incompatibilities caused by failure to include <netdb.h> in existing source code, a #pragma map statement for this function is also available in <sys/types.h> .

EXAMPLE

This program uses the socket call, gethostname to return the hostname as defined to the local host. The local host must have an operational TCPIP stack.

#include <stdlib.h>
#include <netdb.h>
#include <stdio.h>

main()
{
   char buf[128];

/* gethostname returns the hostname in the buf array. If       */
/* gethostname() succeeds it returns a 0, otherwise a -1 and   */
/* errno is set accordingly.                                   */
   if (gethostname(buf,sizeof(buf))) {
      perror("Can't retrive host name");
      return EXIT_FAILURE;
   }
   printf("%s\n",buf);
   return EXIT_SUCCESS;
}

RELATED FUNCTIONS

gethostbyname , gethostid

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