GETPROTOENT(3n,L)           AIX Technical Reference           GETPROTOENT(3n,L)



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getprotoent, getprotobynumber, getprotobyname, setprotoent, endprotoent



PURPOSE

Gets protocol entry.

LIBRARY

Internet Library (libc.a)

SYNTAX

#include <netdb.h>



      struct protoent *getprotoent ( )           void setprotoent (stayopen)
                                                 int stayopen;
      struct protoent *getprotobyname (name)
      char *name;                                void endprotoent ( )

      struct protoent *getprotobynumber (proto)
      int proto;



DESCRIPTION

The getprotoent, getprotobyname, and getprotobynumber subroutines each return a
pointer to an object.  This object is a protoent structure, which contains the
field of a line in the /etc/protocols file (the network protocol data base).
The protoent structure is defined in the netdb.h header file, and it contains
the following members:

      char    *p_name;        /* official name of protocol */
      char    **p_aliases;    /* alias list                */
      long    p_proto;        /* protocol number           */

The members of the structure are defined below:

p_name  Official name of the protocol.

p_aliases
        An array, terminated by a 0, of alternate names for the protocol.

p_proto The protocol number.

The getprotoent subroutine reads the next line of the file.  If the file is not
open, getprotoent opens it.



Processed July 12, 1991        GETPROTOENT(3n,L)                              1






GETPROTOENT(3n,L)           AIX Technical Reference           GETPROTOENT(3n,L)




The setprotoent subroutine opens and rewinds the file.  If the stayopen
parameter is 0, the protocol data base is closed after each call to
getprotobyname or getprotobynumber.  Otherwise, the file is not closed after
each call.

The endprotoent subroutine closes the file.

The getprotobyname and getprotobynumber subroutines search the file
sequentially from its beginning until finding a matching protocol name or
protocol number, or until encountering the end of the file.

RETURN VALUE

A pointer to a protoent structure is returned on success.

Note:  The return value points to static data that is overwritten by subsequent
       calls.

A NULL pointer (0) is returned if an error occurs or the end of the file is
reached.

FILE

/etc/protocols
            Protocol name data base.

RELATED INFORMATION

The discussion of /etc/protocols in AIX TCP/IP User's Guide.

























Processed July 12, 1991        GETPROTOENT(3n,L)                              2