Function copyfileobj

Lib/shutil.py:249–257

copy data from file-like object fsrc to file-like object fdst

(fsrc, fdst, length=0)

                fdst_write(mv)

def copyfileobj(fsrc, fdst, length=0):
    """copy data from file-like object fsrc to file-like object fdst"""
    if not length:
        length = COPY_BUFSIZE
    # Localize variable access to minimize overhead.
    fsrc_read = fsrc.read
    fdst_write = fdst.write
    while buf := fsrc_read(length):
        fdst_write(buf)

def _samefile(src, dst):
    # Macintosh, Unix.