GETPROTOENT(3)		   Linux Programmers Manual	       GETPROTOENT(3)



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

SYNOPSIS
       #include 

       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/pro
       tocols  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  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
       4.3BSD, POSIX.1-2001.

SEE ALSO
       getnetent(3), getservent(3), protocols(5)

COLOPHON
       This  page  is  part of release 3.05 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/.



GNU				  1993-04-24			GETPROTOENT(3)