NAME

memmove — copy bytes in memory with overlapping areas

SYNOPSIS

#include <string.h>

void *memmove(void *s1, const void *s2, size_t n);


DESCRIPTION

^[CX] The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here and the ISO C standard is unintentional. This volume of POSIX.1-2024 defers to the ISO C standard.

The memmove() function shall copy n bytes from the object pointed to by s2 into the object pointed to by s1. Copying takes place as if the n bytes from the object pointed to by s2 are first copied into a temporary array of n bytes that does not overlap the objects pointed to by s1 and s2, and then the n bytes from the temporary array are copied into the object pointed to by s1.

^[CX] The memmove() function shall not change the setting of errno on valid input.

RETURN VALUE

The memmove() function shall return s1; no return value is reserved to indicate an error.

ERRORS

No errors are defined.

EXAMPLES

None.

APPLICATION USAGE

None.

RATIONALE

None.

FUTURE DIRECTIONS

None.

SEE ALSO

XBD <string.h>

CHANGE HISTORY

First released in Issue 4. Derived from the ANSI C standard.

Issue 8

Austin Group Defect 448 is applied, adding a requirement that memmove() does not change the setting of errno on valid input.