The
getprotoent()
function reads the next entry from the protocols database (see
protocols(5))
and returns a protoent structure
containing the broken-out fields from the entry.
A connection is opened to the database if necessary.
The
getprotobyname()
function returns a protoent structure
for the entry from the database
that matches the protocol name name.
A connection is opened to the database if necessary.
The
getprotobynumber()
function returns a protoent structure
for the entry from the database
that matches the protocol number number.
A connection is opened to the database if necessary.
The
setprotoent()
function opens a connection to the database,
and sets the next entry to the first entry.
If stayopen is nonzero,
then the connection to the database
will not be closed between calls to one of the
getproto*()
functions.
The
endprotoent()
function closes the connection to the database.
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 NULL-terminated list of alternative names for the protocol.
p_proto
The protocol number.
RETURN VALUE
The
getprotoent(),
getprotobyname()
and
getprotobynumber()
functions return a pointer to a
statically allocated protoent structure, or a NULL pointer if an
error occurs or the end of the file is reached.
This page is part of release 3.27 of the Linux
man-pages
project.
A description of the project,
and information about reporting bugs,
can be found at
http://www.kernel.org/doc/man-pages/.