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 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 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 (getnetent_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).

ATTRIBUTES

       For an explanation of the terms used in this section, see attributes(7).

       ┌──────────────────┬───────────────┬────────────────┐
       │Interface         │ Attribute     │ Value          │
       ├──────────────────┼───────────────┼────────────────┤
       │getnetent_r(),    │ Thread safety │ MT-Safe locale │
       │getnetbyname_r(), │               │                │
       │getnetbyaddr_r()  │               │                │
       └──────────────────┴───────────────┴────────────────┘

CONFORMING TO

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

SEE ALSO

       getnetent(3), networks(5)

COLOPHON

       This  page  is  part  of  release  4.04  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/.