pager.py 文件源码

def start_pager():
    if not sys.stdout.isatty():
        return

    pager = get_pager()
    if not pager:
        return

    if "LESS" not in os.environ:
        os.environ["LESS"] = "FRSX"

    oldstdout = os.dup(1)
    global pagerproc
    pagerproc = subprocess.Popen([pager],
                                 stdin=subprocess.PIPE,
                                 stdout=oldstdout,
                                 close_fds=True)

    os.close(oldstdout)
    os.dup2(pagerproc.stdin.fileno(), 1)