memmove - Man Page

copy bytes in memory with overlapping areas


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.


#include <string.h>

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


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.1-2017 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.

Return Value

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


No errors are defined.

The following sections are informative.



Application Usage




Future Directions


See Also

The Base Definitions volume of POSIX.1-2017, <string.h>

Referenced By


2017 IEEE/The Open Group POSIX Programmer's Manual