The Get Host Node Name routine returns the host node name of the
    local system.

    Format

      LIB$GET_HOSTNAME  hostname [,resultant-length] [,flags]

1  –  Returns

    OpenVMS usage:cond_value
    type:         longword (unsigned)
    access:       write only
    mechanism:    by value

2  –  Arguments

 hostname

    OpenVMS usage:char_string
    type:         character string
    access:       write only
    mechanism:    by descriptor

    The host node name. The hostname argument contains the address
    of a descriptor pointing to the host node name. LIB$GET_HOSTNAME
    writes the host node-name string into the buffer pointed to by
    the hostname descriptor.

    The error LIB$_INVSTRDES is returned if hostname is an invalid
    descriptor.

    The length field of the hostname descriptor is not updated unless
    hostname is a dynamic descriptor with a length less than the
    host node name to be returned. Refer to the OpenVMS RTL String
    Manipulation (STR$) Manual for dynamic string descriptor usage.

    The hostname argument contains an unusable result when LIB$GET_
    HOSTNAME returns in error.

 resultant-length

    OpenVMS usage:word_unsigned
    type:         word (unsigned)
    access:       write only
    mechanism:    by reference

    Length of the host node name. The resultant-length argument is
    the address of an unsigned word that contains this length in
    bytes.

    The resultant-length argument contains an unusable result when
    LIB$GET_HOSTNAME returns in error.

 flags

    OpenVMS usage:mask_longword
    type:         longword (unsigned)
    access:       read only
    mechanism:    by value

    The value LIB$GET_HOSTNAME uses to control the form of the host
    node name that it returns in the output descriptor hostname. If
    flags is equal to 0, or if flags is omitted, the host node name
    returned is in the network usable form. If flags is equal to 1,
    the host node name returned is in the parsable form.

    Unused bits in flags must be 0. Nonzero unused bits result in the
    error condition LIB$_INVARG.