ETHERS(3N-BSD)      RISC/os Reference Manual       ETHERS(3N-BSD)



NAME
     ethers: ether_ntoa, ether_aton, ether_ntohost,
          ether_hostton, ether_line - Ethernet address mapping
          operations

SYNOPSIS
   Headers
     For -systype svr3:

     #include <sys/types.h>
     #include <bsd/sys/socket.h>
     #include <bsd/net/if.h>
     #include <bsd/netinet/in.h>
     #include <bsd/netinet/if_ether.h>

     For -systype bsd43:

     #include <sys/socket.h>
     #include <net/if.h>
     #include <netinet/in.h>
     #include <netinet/if_ether.h>

   Declarations
     char *
     ether_ntoa(e)
          struct ether_addr *e;

     struct ether_addr *
     ether_aton(s)
          char *s;
     ether_ntohost(hostname, e)
          char *hostname;
          struct ether_addr *e;

     ether_hostton(hostname, e)
          char *hostname;
          struct ether_addr *e;
     ether_line(l, e, hostname)
          char *l;
          struct ether_addr *e;
          char *hostname;

DESCRIPTION
     These routines are useful for mapping 48 bit Ethernet
     numbers to their ASCII representations or their correspond-
     ing host names, and vice versa.

     The function ether_ntoa converts a 48 bit Ethernet number
     pointed to by e to its standard ASCII representation; it
     returns a pointer to the ASCII string.  The representation
     is of the form: ``x:x:x:x:x:x'' where x is a hexadecimal
     number between 0 and ff.  The function ether_aton converts



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ETHERS(3N-BSD)      RISC/os Reference Manual       ETHERS(3N-BSD)



     an ASCII string in the standard representation back to a 48
     bit Ethernet number;  the function returns NULL if the
     string cannot be scanned successfully.

     The function ether_ntohost maps an Ethernet number (pointed
     to by e) to its associated hostname.  The string pointed to
     by hostname must be long enough to hold the hostname and a
     null character.  The function returns zero upon success and
     non-zero upon failure.  Inversely, the function
     ether_hostton maps a hostname string to its corresponding
     Ethernet number; the function modifies the Ethernet number
     pointed to by e.  The function also returns zero upon suc-
     cess and non-zero upon failure.

     The function ether_line scans a line (pointed to by l) and
     sets the hostname and the Ethernet number (pointed to by e).
     The string pointed to by hostname must be long enough to
     hold the hostname and a null character.  The function
     returns zero upon success and non-zero upon failure.  The
     format of the scanned line is described by ethers(4).

FILES
     /etc/ethers    (or the Network Information Service maps
                    ethers.byaddr and ethers.byname)

SEE ALSO
     ethers(4).

NOTE
     When these routines are used in a program which is compiled
     in -systype svr3, they are not resolved by libc.a.  See
     intro(3) for more information.























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