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 (consult 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 net-
work 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 con-
verted from host to network byte order.
The ntohl() and ntohs() functions shall return the argument value con-
verted 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 getservent().
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
endhostent(), endservent()
The Base Definitions volume of POSIX.1-2008, <arpa_inet.h>, <int-
types.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri-
cal and Electronics Engineers, Inc and The Open Group. (This is
POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) 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.unix.org/online.html .
Any typographical or formatting errors that appear in this page are
most likely to have been introduced during the conversion of the source
files to man page format. To report such errors, see https://www.ker-
nel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group 2013 HTONL(3P)