Searches the hosts database that is referenced by the TCPIP$HOST logical name for a host record with the specified name or alias. If the host record is not found, this function may also invoke the BIND resolver to query the appropriate name server for the information. The $QIO equivalent is the IO$_ACPCONTROL function with the INETACP_FUNC$C_GETHOSTBYNAME subfunction code. Format #include <netdb.h> struct hostent *gethostbyname ( char *name );
1 – Argument
name A pointer to a null-terminated character string containing the name or an alias of the host being sought.
2 – Description
This function finds the first host with the specified name or alias in the hosts database, or using DNS/BIND. The gethostbyname() function uses a common static area for its return values. This means that subsequent calls to this function overwrite previously returned host entries. You must make a copy of the host entry if you want to save it.
3 – Return Values
x A pointer to an object having the hostent structure. NULL Indicates an error. errno is set to one of the following values.
4 – Errors
ENETDOWN TCP/IP Services was not started. HOST_NOT_FOUND Host is unknown. NO_DATA The server recognized the request and the name, but no address is available for the name. Another type of name server request may be successful. NO_RECOVERY An unexpected server failure occurred. This is a nonrecoverable error. TRY_AGAIN A transient error occurred; for example, the server did not respond. A retry may be successful.