Section: POSIX Programmer's Manual (0P)
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.
--- sockets local interfaces
header shall define the
structure, which shall include at least the following members:
unsigned if_index Numeric index of the interface.
char *if_name Null-terminated name of the interface.
header shall define the following symbolic constant for the length of
a buffer containing an interface name (including the terminating NULL
Interface name length.
The following shall be declared as functions and may also be defined as
macros. Function prototypes shall be provided.
void if_freenameindex(struct if_nameindex *);
char *if_indextoname(unsigned, char *);
struct if_nameindex *if_nameindex(void);
unsigned if_nametoindex(const char *);
The following sections are informative.
The System Interfaces volume of POSIX.1-2017,
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1-2017, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, 2018 Edition,
Copyright (C) 2018 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group.
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
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