redhat man page for getprotobyname

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

NAME
       getprotoent, getprotobyname, getprotobynumber, setprotoent, endprotoent - 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/protocols 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)