endservent

Purpose

     Gets service entry.

Library

     Sockets Library (libsock.a)

Syntax

     #include <netdb.h>

     struct servent *getservent ( )            void setservent (stayopen)
                                               int stayopen;
     struct servent *getservbyname (name, proto)
     char *name, *proto;                       void endservent ( )

     struct servent *getservbyport (port, proto)
     int port;
     char *proto;
     Description

     The getservent, getservbyname,  and getservbyport subrou-
     tines each return a pointer to an object.  This object is
     a servent structure,  which contains the field  of a line
     in  the /etc/services  file  (the  network services  data
     base).  The  servent structure is defined  in the netdb.h
     header file, and it contains the following members:

          char    *s_name;      /* official name of service   */
          char    **s_aliases;  /* alias list                 */
          long    s_port;       /* port where service resides */
          char    *s_proto;     /* protocol to use            */

     The members of the structure are defined below:

     s_name      Official name of the service.

     s_aliases   An  array, terminated  by a  0, of  alternate
                 names for the service.

     s_port      The port number at which the service resides.
                 Port  numbers are  returned  in network  byte
                 order.

     s_proto     The  name of  the protocol  to use  when con-
                 tacting the service.

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

     The setservent subroutine opens and rewinds the file.  If
     the stayopen  parameter is  0, the  service data  base is
     closed  after each  call to  getservent.  Otherwise,  the
     file is not closed after each call.

     The endservent subroutine closes the file.

     The  getservbyname and  getservbyport subroutines  search
     the file sequentially from  its beginning until finding a
     matching protocol name or  port number, or until encount-
     ering the end of the file.   When a protocol name is also
     supplied, searches also match the protocol.

     Return Value

     A pointer to a servent 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/services   Service name data base.

     Related Information

     In   this   book:       "getprotoent,   getprotobynumber,
     getprotobyname, setprotoent, endprotoent."

     The discussion of /etc/services  in Interface Program for
     use with TCP/IP.