这是一个演示日志切割的python程序

logging.py

#!/usr/bin/python3
# -*- coding: UTF-8 -*-
#================================================================================
# 这是一个演示日志切割的python程序
# 作者: netkiller | netkiller@msn.com | http://www.netkiller.cn
#================================================================================

import time,os,signal,sys

pidfile = "/tmp/netkiller.pid"
logdir = "/tmp"
logfile = open("/dev/null", "a+")
loop = True

def savepid(pid):
    f = open(pidfile,"w")
    f.write(pid)
    f.flush()
    f.close()
def getpid():
    f = open(pidfile,"r")
    pid = f.readline()
    f.close()
    # print(pid)
    return int(pid)
def createlog():
    global logfile
    logfile.flush()
    logfile.close()
    filename = time.strftime(logdir + "/netkiller-%Y-%m-%d.%H-%M-%S.log",time.localtime());
    # print(filename)
    logfile = open(filename,mode="a+")
    return filename
def log(tag,msg):
    logfile.write(time.strftime("%Y-%m-%d %H:%M:%S",time.localtime()) + " "+tag+" "+ msg +"\r\n")
    logfile.flush()

def signalHandler(signum,frame):
    global loop
    # print("HUP OK",str(signum));
    if signum == signal.SIGHUP :
        filename = createlog()
        log("WARN","Create log file " + filename)
    elif signum == signal.SIGINT:
        loop = False

def start():
    if os.path.isfile(pidfile) :
        print("error")
        sys.exit()
    pid = os.fork()

    if pid == 0 :
        # print(os.getpid())
        savepid(str(os.getpid()))
        createlog()
        log("WARN","Start!!!")
        while loop:
            # 业务逻辑
            log("INFO","Hello world!!!")
            # 业务逻辑
            time.sleep(1)
        log("WARN","Exit!!!")
        logfile.close()

def stop():
    try:
        os.kill(getpid(), signal.SIGINT) 
    except ProcessLookupError as identifier:
        pass
    os.remove(pidfile)
    

def reloadlog():
    try:
        os.kill(getpid(), signal.SIGHUP) 
    except ProcessLookupError as identifier:
        pass
    

def usage():
    print(sys.argv[0] + " start | stop | reload")

if __name__ == "__main__":
    # print(sys.argv)
    signal.signal(signal.SIGHUP, signalHandler)
    signal.signal(signal.SIGINT, signalHandler)
    signal.alarm(5)

    if len(sys.argv) > 1:
        arg = sys.argv[1]
        if arg == "start" :
            start()
        elif arg == "stop":
            stop()
        elif arg == "reload":
            reloadlog()
        else:
            usage()
    else: 
        usage()