HTONL(3P)                                           POSIX Programmer's Manual                                          HTONL(3P)



PROLOG
       This  manual  page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (con-
       sult the corresponding Linux manual page for details of Linux behavior), or the  interface  may  not  be  implemented  on
       Linux.

NAME
       htonl, htons, ntohl, ntohs - convert values between host and network byte order

SYNOPSIS
       #include <arpa/inet.h>

       uint32_t htonl(uint32_t hostlong);
       uint16_t htons(uint16_t hostshort);
       uint32_t ntohl(uint32_t netlong);
       uint16_t ntohs(uint16_t netshort);


DESCRIPTION
       These functions shall convert 16-bit and 32-bit quantities between network byte order and host byte order.

       On some implementations, these functions are defined as macros.

       The uint32_t and uint16_t types are defined in <inttypes.h>.

RETURN VALUE
       The htonl() and htons() functions shall return the argument value converted from host to network byte order.

       The ntohl() and ntohs() functions shall return the argument value converted from network to host byte order.

ERRORS
       No errors are defined.

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       These  functions are most often used in conjunction with IPv4 addresses and ports as returned by gethostent() and getser-
       vent().

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       endhostent(), endservent(), the Base Definitions volume of IEEE Std 1003.1-2001, <inttypes.h>, <arpa/inet.h>

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003  Edition,  Standard  for
       Information  Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copy-
       right (C) 2001-2003 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   http://www.open-
       group.org/unix/online.html .



IEEE/The Open Group                                           2003                                                     HTONL(3P)