如何从脚本内部做到这一点？
更新 ：要正确地守护进程，请使用守护进程。
原始答案 ：因为shell正在等待你的进程完成，所以主进程必须终止。 你可以使用os.fork() sys.exit()从父进程中分离一个子进程和sys.exit() ：
import os import sys if os.fork(): sys.exit() # Child code goes here
复制相关代码以Python方式创建守护进程 ; 请阅读关于为什么代码是相当深思熟虑的意见。
def createDaemon(): """Detach a process from the controlling terminal and run it in the background as a daemon. """ try: # Fork a child process so the parent can exit. This returns control to # the command-line or shell. It also guarantees that the child will not # be a process group leader, since the child receives a new process ID # and inherits the parent's process group ID. This step is required # to insure that the next call to os.setsid is successful. pid = os.fork() except OSError, e: raise Exception, "%s [%d]" % (e.strerror, e.errno) if (pid == 0): # The first child. # To become the session leader of this new session and the process group # leader of the new process group, we call os.setsid(). The process is # also guaranteed not to have a controlling terminal. os.setsid() # Is ignoring SIGHUP necessary? # # It's often suggested that the SIGHUP signal should be ignored before # the second fork to avoid premature termination of the process. The # reason is that when the first child terminates, all processes, eg # the second child, in the orphaned group will be sent a SIGHUP. # # "However, as part of the session management system, there are exactly # two cases where SIGHUP is sent on the death of a process: # # 1) When the process that dies is the session leader of a session that # is attached to a terminal device, SIGHUP is sent to all processes # in the foreground process group of that terminal device. # 2) When the death of a process causes a process group to become # orphaned, and one or more processes in the orphaned group are # stopped, then SIGHUP and SIGCONT are sent to all members of the # orphaned group." [2] # # The first case can be ignored since the child is guaranteed not to have # a controlling terminal. The second case isn't so easy to dismiss. # The process group is orphaned when the first child terminates and # POSIX.1 requires that every STOPPED process in an orphaned process # group be sent a SIGHUP signal followed by a SIGCONT signal. Since the # second child is not STOPPED though, we can safely forego ignoring the # SIGHUP signal. In any case, there are no ill-effects if it is ignored. # # import signal # Set handlers for asynchronousous events. # signal.signal(signal.SIGHUP, signal.SIG_IGN) try: # Fork a second child and exit immediately to prevent zombies. This # causes the second child process to be orphaned, making the init # process responsible for its cleanup. And, since the first child is # a session leader without a controlling terminal, it's possible for # it to acquire one by opening a terminal in the future (System V- # based systems). This second fork guarantees that the child is no # longer a session leader, preventing the daemon from ever acquiring # a controlling terminal. pid = os.fork() # Fork a second child. except OSError, e: raise Exception, "%s [%d]" % (e.strerror, e.errno) if (pid == 0): # The second child. # Since the current working directory may be a mounted filesystem, we # avoid the issue of not being able to unmount the filesystem at # shutdown time by changing it to the root directory. os.chdir(WORKDIR) # We probably don't want the file mode creation mask inherited from # the parent, so we give the child complete control over permissions. os.umask(UMASK) else: # exit() or _exit()? See below. os._exit(0) # Exit parent (the first child) of the second child. else: # exit() or _exit()? # _exit is like exit(), but it doesn't call any functions registered # with atexit (and on_exit) or any registered signal handlers. It also # closes any open file descriptors. Using exit() may cause all stdio # streams to be flushed twice and any temporary files may be unexpectedly # removed. It's therefore recommended that child branches of a fork() # and the parent branch(es) of a daemon use _exit(). os._exit(0) # Exit parent of the first child.