GETPROTOENT(3) System Library Functions Manual GETPROTOENT(3)
+
+NAME
+ getprotoent, getprotobynumber, getprotobyname, setprotoent, endprotoent -
+ get protocol entry
+
+SYNOPSIS
+ #include <netdb.h>
+
+ struct protoent *
+ getprotoent(void);
+
+ struct protoent *
+ getprotobyname(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 database,
+ /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 database will not be closed after each call to
+ getprotobyname() or getprotobynumber().
+
+ The endprotoent() function closes the file.
+
+ The getprotobyname() and getprotobynumber() functions 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 (0) 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 static 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.
+
+BSD June 4, 1993 BSD
+ |