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	*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.

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 end-of-file is encountered.

FILES
/etc/protocols

SEE ALSO
protocols(5), ypserv(8)

DIAGNOSTICS
A NULL pointer is returned on end-of-file or error.

BUGS
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.