Gethostbyname

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gethostbyname (IXCALL 0x3E27) - get network host entry

Synopsis

Assembly language

   ld hl, STR_HOSTNAME
   ld de, BUF_ADDRESS
   ld ix, GETHOSTBYNAME
   call IXCALL

C

   #include <netdb.h>

   struct hostent *gethostbyname(char *name);

Description

The gethostbyname() call converts the string passed in name to an address. The parameter name may be a null-terminated hostname (such as 'www.worldofspectrum.org' or a null-terminated dotted decimal string representation of an IP address. If a dotted decimal address is passed, no lookup is made, and the string is converted to a 4 byte big-endian representation of the address. If a hostname is passed, the hostname is looked up using the DNS protocol, and the resolved address is returned as a 4 byte big-endian value. With the current implementation, only one address is returned on a successful lookup.

For the C function call, the pointer returned is to a statically allocated buffer. If the value returned needs to be preserved when a subsequent call to gethostbyname() is made, the value must be copied before the next call is made.

For the assembly language interface, the register pair HL points to a null-terminated string containing the hostname or dotted decimal IP address, and the DE register pair points to a location in memory with at least 4 bytes free to receive the 4 byte big-endian representation of the address.

Return values

The C interface returns a null pointer if gethostbyname() fails to resolve the address.

The assembly language interface returns with the carry flag set on error, with the A register containing the return code.