getprotoent

GETPROTOENT(3)		  Linux Programmer’s Manual	       GETPROTOENT(3)



NAME
       getprotoent,  getprotobyname,  getprotobynumber,	 setprotoent, endpro-
       toent - get protocol entry

SYNOPSIS
       #include <netdb.h>

       struct protoent *getprotoent(void);

       struct protoent *getprotobyname(const char *name);

       struct protoent *getprotobynumber(int proto);

       void setprotoent(int stayopen);

       void endprotoent(void);

DESCRIPTION
       The getprotoent() function reads the next line from the file /etc/pro-
       tocols  and  returns  a	structure  protoent containing the broken out
       fields from the line.  The /etc/protocols file is opened if necessary.

       The  getprotobyname()  function	returns	 a protoent structure for the
       line from /etc/protocols that matches the protocol name name.

       The getprotobynumber() function returns a protoent structure  for  the
       line that matches the protocol number number.

       The  setprotoent() function opens and rewinds the /etc/protocols file.
       If stayopen is true (1), then the file  will  not  be  closed  between
       calls to getprotobyname() or getprotobynumber().

       The endprotoent() function closes /etc/protocols.

       The protoent structure is defined in <netdb.h> as follows:

	      struct protoent {
		      char    *p_name;	      /* official protocol name */
		      char    **p_aliases;    /* alias list */
		      int     p_proto;	      /* protocol number */
	      }

       The members of the protoent structure are:

       p_name The official name of the protocol.

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

       p_proto
	      The protocol number.

RETURN VALUE
       The  getprotoent(),  getprotobyname() and getprotobynumber() functions
       return the protoent structure, or a NULL pointer if an error occurs or
       the end of the file is reached.

FILES
       /etc/protocols
	      protocol database file

CONFORMING TO
       BSD 4.3

SEE ALSO
       getservent(3), getnetent(3), protocols(5)



BSD				  1993-04-24		       GETPROTOENT(3)