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ENDNETENT(3P)              POSIX Programmer's Manual             ENDNETENT(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
       endnetent, getnetbyaddr, getnetbyname, getnetent, setnetent --  network
       database functions
SYNOPSIS
       #include <netdb.h>
       void endnetent(void);
       struct netent *getnetbyaddr(uint32_t net, int type);
       struct netent *getnetbyname(const char *name);
       struct netent *getnetent(void);
       void setnetent(int stayopen);
DESCRIPTION
       These  functions shall retrieve information about networks. This infor-
       mation is considered to be stored in a database that  can  be  accessed
       sequentially  or  randomly.  The  implementation  of  this  database is
       unspecified.
       The setnetent() function shall open and rewind  the  database.  If  the
       stayopen argument is non-zero, the connection to the net database shall
       not be closed after each call to getnetent() (either directly, or indi-
       rectly through one of the other getnet*() functions), and the implemen-
       tation may maintain an open file descriptor to the database.
       The getnetent() function shall read the next  entry  of  the  database,
       opening and closing a connection to the database as necessary.
       The  getnetbyaddr()  function shall search the database from the begin-
       ning, and find the first entry for which the address  family  specified
       by  type  matches  the  n_addrtype  member  and  the network number net
       matches the n_net member, opening and closing a connection to the data-
       base  as  necessary.   The  net argument shall be the network number in
       host byte order.
       The getnetbyname() function shall search the database from  the  begin-
       ning  and  find the first entry for which the network name specified by
       name matches the n_name member, opening and closing a connection to the
       database as necessary.
       The  getnetbyaddr(),  getnetbyname(),  and  getnetent() functions shall
       each return a pointer to a netent structure, the members of which shall
       contain the fields of an entry in the network database.
       The  endnetent()  function shall close the database, releasing any open
       file descriptor.
       These functions need not be thread-safe.
RETURN VALUE
       Upon successful completion, getnetbyaddr(), getnetbyname(), and  getne-
       tent()  shall  return  a pointer to a netent 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 shall be returned.
       The application shall not modify the  structure  to  which  the  return
       value  points,  nor any storage areas pointed to by pointers within the
       structure. The returned pointer, and  pointers  within  the  structure,
       might  be  invalidated  or  the structure or the storage areas might be
       overwritten by a subsequent call to getnetbyaddr(), getnetbyname(),  or
       getnetent().
ERRORS
       No errors are defined.
       The following sections are informative.
EXAMPLES
       None.
APPLICATION USAGE
       None.
RATIONALE
       None.
FUTURE DIRECTIONS
       None.
SEE ALSO
       The Base Definitions volume of POSIX.1-2008, <netdb.h>
COPYRIGHT
       Portions  of  this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
       --  Portable  Operating  System  Interface (POSIX), The Open Group Base
       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri-
       cal  and  Electronics  Engineers,  Inc  and  The  Open Group.  (This is
       POSIX.1-2008 with the 2013 Technical Corrigendum  1  applied.)  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.unix.org/online.html .
       Any typographical or formatting errors that appear  in  this  page  are
       most likely to have been introduced during the conversion of the source
       files to man page format. To report such errors,  see  https://www.ker-
       nel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group                  2013                        ENDNETENT(3P)