inet_addr()

Convert a string into a numeric Internet address

Synopsis:

#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

in_addr_t inet_addr( const char * cp );

Arguments:

cp
A pointer to a string that represents an Internet address.

Library:

libsocket

Use the -l socket option to qcc to link against this library.

Description:

The inet_addr() routine converts a string representing an IPv4 Internet address (for example, "127.0.0.1") into a numeric Internet address. To convert a hostname such as ftp.qnx.com, call gethostbyname() .

All Internet addresses are returned in network byte order (bytes are ordered from left to right). All network numbers and local address parts are returned as machine-format integer values. For more information on Internet addresses, see inet_net_ntop() .

Returns:

An Internet address, or INADDR_NONE if an error occurs.

Classification:

POSIX 1003.1

Safety:  
Cancellation point No
Interrupt handler No
Signal handler Yes
Thread Yes

Caveats:

Although the value INADDR_NONE (0xFFFFFFFF) is a valid broadcast address, inet_addr() always indicates failure when returning that value. The inet_aton() function doesn't share this problem.

Last modified: 2013-12-23

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