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       getnetent_r,   getnetbyname_r,   getnetbyaddr_r  -  get  network  entry


       #include <netdb.h>

       int getnetent_r(struct netent *result_buf, char *buf,
                       size_t buflen, struct netent **result,
                       int *h_errnop);

       int getnetbyname_r(const char *name,
                       struct netent *result_buf, char *buf,
                       size_t buflen, struct netent **result,
                       int *h_errnop);

       int getnetbyaddr_r(uint32_t net, int type,
                       struct netent *result_buf, char *buf,
                       size_t buflen, struct netent **result,
                       int *h_errnop);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       getnetent_r(), getnetbyname_r(), getnetbyaddr_r(): _BSD_SOURCE ||


       The getnetent_r(), getnetbyname_r(), and getnetbyaddr_r() functions are
       the   reentrant    equivalents    of,    respectively,    getnetent(3),
       getnetbyname(3),  and  getnetbynumber(3).   They differ in the way that
       the netent structure is returned, and in the function calling signature
       and return value.  This manual page describes just the differences from
       the nonreentrant functions.

       Instead of  returning  a  pointer  to  a  statically  allocated  netent
       structure  as  the  function result, these functions copy the structure
       into the location pointed to by result_buf.

       The buf array is used to store the string  fields  pointed  to  by  the
       returned  netent structure.  (The nonreentrant functions allocate these
       strings in static storage.)  The size of this  array  is  specified  in
       buflen.  If buf is too small, the call fails with the error ERANGE, and
       the caller must try again with a larger buffer.  (A  buffer  of  length
       1024 bytes should be sufficient for most applications.)

       If  the  function  call  successfully  obtains  a  network record, then
       *result is set pointing to result_buf; otherwise,  *result  is  set  to

       The  buffer  pointed  to  by  h_errnop is used to return the value that
       would be stored in the global  variable  h_errno  by  the  nonreentrant
       versions of these functions.


       On  success,  these  functions  return  0.   On error, a positive error
       number is returned.

       On error, record not found (getnetbyname_r(), getnetbyaddr_r()), or end
       of input (getnetent_r()) result is set to NULL.


       ENOENT (getnetent_r()) No more records in database.

       ERANGE buf is too small.  Try again with a larger buffer (and increased


       These functions are GNU extensions.  Functions with similar names exist
       on   some  other  systems,  though  typically  with  different  calling


       getnetent(3), networks(5)


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