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, 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.
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 systems, though typically with different calling
signatures.
SEE ALSO
getnetent(3), networks(5)
COLOPHON
This page is part of release 3.24 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.