htonl(3p) — Linux manual page

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

PROLOG         top

       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         top

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

SYNOPSIS         top

       #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         top

       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         top

       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         top

       No errors are defined.

       The following sections are informative.

EXAMPLES         top

       None.

APPLICATION USAGE         top

       These functions are most often used in conjunction with IPv4
       addresses and ports as returned by gethostent() and getservent().

RATIONALE         top

       None.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       endhostent(3p), endservent(3p)

       The Base Definitions volume of POSIX.1‐2017, arpa_inet.h(0p),
       inttypes.h(0p)

COPYRIGHT         top

       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
       http://www.opengroup.org/unix/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.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                2017                         HTONL(3P)

Pages that refer to this page: arpa_inet.h(0p),  netinet_in.h(0p),  endservent(3p),  ntohl(3p)

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