getprotoent(3N)                  UNIX System V                  getprotoent(3N)


NAME
      getprotoent, getprotobynumber, getprotobyname, setprotoent, endprotoent -
      get protocol entry

SYNOPSIS
      #include <netdb.h>
      struct protoent *getprotoent(void);
      struct protoent *getprotobyname(char *name);
      struct protoent *getprotobynumber(int proto);
      int setprotoent(int stayopen);
      int endprotoent(void);

DESCRIPTION
      getprotoent, getprotobyname, and getprotobynumber each return a pointer
      to an object with the following structure containing the broken-out
      fields of a line in the network protocol data base, /etc/protocols.

      The protoent structure include the following members:
            char   *pname;        /* official name of protocol */
            char   **paliases;    /* alias list */
            int    pproto;        /* protocol number */

      The members of this structure are:

            p_name              The official name of the protocol.

            p_aliases           A zero terminated list of alternate names for
                                the protocol.

            p_proto             The protocol number.

      getprotoent reads the next line of the file, opening the file if
      necessary.

      setprotoent opens and rewinds the file.  If the stayopen flag is non-
      zero, the net data base will not be closed after each call to getprotoent
      (either directly, or indirectly through one of the other getproto calls).

      endprotoent closes the file.

      getprotobyname and getprotobynumber sequentially search from the
      beginning of the file until a matching protocol name or protocol number
      is found, or until an EOF is encountered.

FILES
      /etc/protocols

SEE ALSO
      protocols(4)





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getprotoent(3N)                  UNIX System V                  getprotoent(3N)


DIAGNOSTICS
      A NULL pointer is returned on an EOF or error.

      All information is contained in a static area so it must be copied if it
      is to be saved.  Only the Internet protocols are currently understood.

















































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