getprotoent(3N)         NETWORK FUNCTIONS         getprotoent(3N)



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

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

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.
          struct    protoent {
               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  begin-
     ning  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)

DIAGNOSTICS
     A NULL pointer is returned on an EOF or error.  All informa-
     tion  is  contained in a static area so it must be copied if



                          Last change:                          1

getprotoent(3N)         NETWORK FUNCTIONS         getprotoent(3N)



     it  is  to  be  saved.   Only  the  Internet  protocols  are
     currently understood.





















































                          Last change:                          2