swab(3) Library Functions Manual swab(3)
NAME
swab - swap adjacent bytes
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#define _XOPEN_SOURCE /* See feature_test_macros(7) */
#include <unistd.h>
void swab(const void from[restrict .n], void to[restrict .n],
ssize_t n);
DESCRIPTION
The swab() function copies n bytes from the array pointed to by from to
the array pointed to by to, exchanging adjacent even and odd bytes.
This function is used to exchange data between machines that have dif-
ferent low/high byte ordering.
This function does nothing when n is negative. When n is positive and
odd, it handles n-1 bytes as above, and does something unspecified with
the last byte. (In other words, n should be even.)
RETURN VALUE
The swab() function returns no value.
ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).
┌────────────────────────────────────────────┬───────────────┬─────────┐
│ Interface │ Attribute │ Value │
├────────────────────────────────────────────┼───────────────┼─────────┤
│ swab() │ Thread safety │ MT-Safe │
└────────────────────────────────────────────┴───────────────┴─────────┘
STANDARDS
POSIX.1-2008.
HISTORY
POSIX.1-2001, SVr4, 4.3BSD.
SEE ALSO
bstring(3)
Linux man-pages 6.9.1 2024-05-02 swab(3)
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