inet_aton()

PROTOTYPE

#include <sockets.h>

int inet_aton(const char strptr, struct in_addr *addrptr);

DESCRIPTION

inet_aton() converts an IPv4 address from an Internet dotted notation string to an integer address in network byte order. addrptr points to a buffer where the converted address is stored. strptr points to the string to be converted, which should have one of the following formats:

          "a" - where a is a 32-bit number,
          "a.b" - where a is an 8-bit number and b is a 24-bit number,
          "a.b.c" - where a and b are 8-bit numbers and c is a 16-bit number, or
          "a.b.c.d" - where a, b, c, and d are 8-bit numbers.

If there is a leading “0x” or “0X”, the numbers are interpreted as hexadecimal. If there is a leading “0”, they are interpreted as octal. Otherwise, the numbers are interpreted as decimal.

inet_aton() returns 1 if the conversion is successful or 0 if it failed.

EXAMPLE

  /***********************************************************************/
  /* getHostByName: Request IP address resolution from DNS server        */
  /*                                                                     */
  /*       Input: name = NULL-terminated host name                       */
  /*                                                                     */
  /*     Returns: IP address if no errors, else 0                        */
  /*                                                                     */
  /***********************************************************************/
  in_addr_t getHostByName(const char *name)
  {
    uint dotted;
    const char *np;
    struct in_addr addr;

    /*-------------------------------------------------------------------*/
    /* Check if name is just address in Internet dotted notation.        */
    /*-------------------------------------------------------------------*/
    if (inet_aton(name, &addr))
      return addr.s_addr;