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ENDSERVENT(3P)             POSIX Programmer's Manual            ENDSERVENT(3P)

PROLOG
       This  manual  page is part of the POSIX Programmer's Manual.  The Linux
       implementation of this interface may differ (consult the  corresponding
       Linux  manual page for details of Linux behavior), or the interface may
       not be implemented on Linux.
NAME
       endservent, getservbyname, getservbyport, getservent, setservent - net-
       work services database functions
SYNOPSIS
       #include <netdb.h>
       void endservent(void);
       struct servent *getservbyname(const char *name, const char *proto);
       struct servent *getservbyport(int port, const char *proto);
       struct servent *getservent(void);
       void setservent(int stayopen);

DESCRIPTION
       These  functions  shall  retrieve  information  about network services.
       This information is considered to be stored in a database that  can  be
       accessed  sequentially or randomly. The implementation of this database
       is unspecified.
       The setservent() function shall open a connection to the database,  and
       set the next entry to the first entry. If the stayopen argument is non-
       zero, the net database shall not be closed after each call to the  get-
       servent()  function  (either directly, or indirectly through one of the
       other getserv*() functions), and the  implementation  may  maintain  an
       open file descriptor for the database.
       The  getservent()  function  shall read the next entry of the database,
       opening and closing a connection to the database as necessary.
       The getservbyname() function shall search the database from the  begin-
       ning  and  find the first entry for which the service name specified by
       name matches the s_name member and the protocol name specified by proto
       matches  the  s_proto  member,  opening and closing a connection to the
       database as necessary. If proto is a null pointer,  any  value  of  the
       s_proto member shall be matched.
       The  getservbyport() function shall search the database from the begin-
       ning and find the first entry for which  the  port  specified  by  port
       matches  the  s_port  member  and  the protocol name specified by proto
       matches the s_proto member, opening and closing  a  connection  to  the
       database  as  necessary.  If  proto is a null pointer, any value of the
       s_proto member shall be matched. The port argument shall be in  network
       byte order.
       The  getservbyname(), getservbyport(), and getservent() functions shall
       each return a pointer to a servent  structure,  the  members  of  which
       shall contain the fields of an entry in the network services database.
       The  endservent() function shall close the database, releasing any open
       file descriptor.
       These functions need not be reentrant. A function that is not  required
       to be reentrant is not required to be thread-safe.
RETURN VALUE
       Upon  successful completion, getservbyname(), getservbyport(), and get-
       servent() return a pointer to a  servent  structure  if  the  requested
       entry  was  found,  and  a  null pointer if the end of the database was
       reached or the requested entry was not found. Otherwise, a null pointer
       is returned.
ERRORS
       No errors are defined.
       The following sections are informative.
EXAMPLES
       None.
APPLICATION USAGE
       The  port  argument  of getservbyport() need not be compatible with the
       port values of all address families.
       The getservbyname(), getservbyport(), and  getservent()  functions  may
       return  pointers to static data, which may be overwritten by subsequent
       calls to any of these functions.
RATIONALE
       None.
FUTURE DIRECTIONS
       None.
SEE ALSO
       endhostent(), endprotoent(), htonl(), inet_addr(), the Base Definitions
       volume of IEEE Std 1003.1-2001, <netdb.h>
COPYRIGHT
       Portions  of  this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
       --  Portable  Operating  System  Interface (POSIX), The Open Group Base
       Specifications Issue 6, Copyright (C) 2001-2003  by  the  Institute  of
       Electrical  and  Electronics  Engineers, Inc and The Open Group. In the
       event of any discrepancy between this version and the original IEEE and
       The  Open Group Standard, the original IEEE and The Open Group Standard
       is the referee document. The original Standard can be  obtained  online
       at http://www.opengroup.org/unix/online.html .

IEEE/The Open Group                  2003                       ENDSERVENT(3P)