byteorder(3) — Linux manual page

BYTEORDER(3)            Library Functions Manual            BYTEORDER(3)

NAME         top

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

LIBRARY         top

       Standard C library (libc, -lc)

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

       The htonl() function converts the unsigned integer hostlong from
       host byte order to network byte order.

       The htons() function converts the unsigned short integer
       hostshort from host byte order to network byte order.

       The ntohl() function converts the unsigned integer netlong from
       network byte order to host byte order.

       The ntohs() function converts the unsigned short integer netshort
       from network byte order to host byte order.

       On the i386 the host byte order is Least Significant Byte first,
       whereas the network byte order, as used on the Internet, is Most
       Significant Byte first.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       ┌─────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                           │ Attribute     │ Value   │
       ├─────────────────────────────────────┼───────────────┼─────────┤
       │ htonl(), htons(), ntohl(), ntohs()  │ Thread safety │ MT-Safe │
       └─────────────────────────────────────┴───────────────┴─────────┘

STANDARDS         top

       POSIX.1-2008.

HISTORY         top

       POSIX.1-2001.

SEE ALSO         top

       bswap(3), endian(3), gethostbyname(3), getservent(3)

COLOPHON         top

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Linux man-pages 6.9.1          2024-05-02                   BYTEORDER(3)

Pages that refer to this page: bswap(3),  endian(3),  inet(3),  pmdacache(3),  sockaddr(3type),  ip(7),  signal-safety(7)

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