GETNETENT_R(3)                      Linux Programmer's Manual                      GETNETENT_R(3)



NAME
       getnetent_r, getnetbyname_r, getnetbyaddr_r - get network entry (reentrant)

SYNOPSIS
       #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 || _SVID_SOURCE

DESCRIPTION
       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 sig‐
       nature and return value.  This manual page describes just the differences  from  the  non‐
       reentrant 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  struc‐
       ture.  (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 NULL.

       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.

RETURN VALUE
       On success, these functions return 0.  On error, they return one  of  the  positive  error
       numbers listed in ERRORS.

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

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

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

CONFORMING TO
       These functions are GNU extensions.  Functions with similar names exist on some other sys‐
       tems, though typically with different calling signatures.

SEE ALSO
       getnetent(3), networks(5)

COLOPHON
       This  page  is  part of release 3.74 of the Linux man-pages project.  A description of the
       project, information about reporting bugs, and the latest version of  this  page,  can  be
       found at http://www.kernel.org/doc/man-pages/.



GNU                                         2010-09-10                             GETNETENT_R(3)