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GETPROTOENT(3)	       FreeBSD Library Functions Manual		GETPROTOENT(3)

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

LIBRARY
     Standard C	Library	(libc, -lc)

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(),	getprotobyname(), and getprotobynumber() functions
     each return a pointer to an object	with the following structure contain-
     ing the broken-out	fields of a line in the	network	protocol data base,
     /etc/protocols.

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

     The getprotoent() function	reads the next line of the file, opening the
     file if necessary.

     The setprotoent() function	opens and rewinds the file.  If	the stayopen
     flag is non-zero, the net data base will not be closed after each call to
     getprotobyname() or getprotobynumber().

     The endprotoent() function	closes the file.

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

RETURN VALUES
     Null pointer returned on EOF or error.

FILES
     /etc/protocols

SEE ALSO
     protocols(5)

HISTORY
     The getprotoent(),	getprotobynumber(), getprotobyname(), setprotoent(),
     and endprotoent() functions appeared in 4.2BSD.

BUGS
     These functions use a thread-specific data	space; if the data is needed
     for future	use, it	should be copied before	any subsequent calls overwrite
     it.  Only the Internet protocols are currently understood.

FreeBSD	13.0			 June 4, 1993			  FreeBSD 13.0

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | FILES | SEE ALSO | HISTORY | BUGS

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