The Open Group Base Specifications Issue 8
IEEE Std 1003.1-2024
Copyright © 2001-2024 The IEEE and The Open Group

NAME

swab — swap bytes

SYNOPSIS

[XSI] [Option Start] #include <unistd.h>

void swab(const void *restrict
src, void *restrict dest,
       ssize_t
nbytes); [Option End]

DESCRIPTION

The swab() function shall copy nbytes bytes, which are pointed to by src, to the object pointed to by dest, exchanging adjacent bytes. The nbytes argument should be even. If nbytes is odd, swab() copies and exchanges nbytes-1 bytes and the disposition of the last byte is unspecified. If copying takes place between objects that overlap, the behavior is undefined. If nbytes is negative, swab() does nothing.

RETURN VALUE

None.

ERRORS

No errors are defined.


The following sections are informative.

EXAMPLES

None.

APPLICATION USAGE

None.

RATIONALE

None.

FUTURE DIRECTIONS

None.

SEE ALSO

XBD <unistd.h>

CHANGE HISTORY

First released in Issue 1. Derived from Issue 1 of the SVID.

Issue 6

The restrict keyword is added to the swab() prototype for alignment with the ISO/IEC 9899:1999 standard.

End of informative text.

 

return to top of page

UNIX® is a registered Trademark of The Open Group.
POSIX™ is a Trademark of The IEEE.
Copyright © 2001-2024 The IEEE and The Open Group, All Rights Reserved
[ Main Index | XBD | XSH | XCU | XRAT ]