---
name: "bcopy"
section: "3"
platform: "macos"
package: "Libc"
version: "1752.120.2"
release: "macOS 26.5"
platforms: ["linux", "freebsd", "macos"]
url: "https://new.carta.tech/bcopy/3"
---

# bcopy(3)

copy byte string

## NAME

**bcopy** – copy byte string

## LIBRARY

Standard C Library (libc, -lc)

## SYNOPSIS

**#include \<strings.h\>**

*void*\

**bcopy**(*const void \*src*, *void \*dst*, *size\_t len*);

## DESCRIPTION

The **bcopy**() function copies *len* bytes from string *src* to string *dst*. The two strings may overlap. If *len* is zero, no bytes are copied.

## SEE ALSO

[memccpy(3)](/memccpy/3.md), [memcpy(3)](/memcpy/3.md), [memmove(3)](/memmove/3.md), [strcpy(3)](/strcpy/3.md), [strncpy(3)](/strncpy/3.md)

## HISTORY

A **bcopy**() function appeared in 4.2BSD. Its prototype existed previously in ⟨string.h⟩ before it was moved to ⟨strings.h⟩ for IEEE Std 1003.1-2001 (“POSIX.1”) compliance.

**bcopy**() was deprecated in IEEE Std 1003.1-2001 (“POSIX.1”) and removed in IEEE Std 1003.1-2008 (“POSIX.1”).