Table of Contents
1. 概念
3. 进程
6. 线程
1. 概念
2. 环境变量
import os
#不换行输出变量
path = os.environ.get("PATH")
print(path)
#换行输出变量
for key in os.environ.keys():
print(key, '\t', os.environ[key])
C:\Python\Python38\python.exe "E:/python/python project/hello world.py"
C:\Python\Python38\Scripts\;C:\Python\Python38\;C:\Python\Python37\Scripts\;C:\Python\Python37\;C:\ProgramData\Oracle\Java\javapath;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Program Files\CMake\bin;C:\Program Files\Git\cmd;C:\Program Files (x86)\Windows Kits\8.1\Windows Performance Toolkit\;C:\Program Files\Microsoft SQL Server\120\Tools\Binn\;D:\Tcl\bin;C:\Python\Python38\Scripts\;C:\Python\Python38\;C:\Python\Python37\Scripts\;C:\Python\Python37\;C:\ProgramData\Oracle\Java\javapath;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Program Files\CMake\bin;C:\Program Files\Git\cmd;C:\Program Files (x86)\Windows Kits\8.1\Windows Performance Toolkit\;C:\Program Files\Microsoft SQL Server\120\Tools\Binn\;d:\Program Files\Docker Toolbox;d:\Program Files\JetBrains\PyCharm 2018.3.5\bin;;C:\Python\Python37;
ALLUSERSPROFILE C:\ProgramData
APPDATA C:\Users\nxbb\AppData\Roaming
COMMONPROGRAMFILES C:\Program Files\Common Files
COMMONPROGRAMFILES(X86) C:\Program Files (x86)\Common Files
COMMONPROGRAMW6432 C:\Program Files\Common Files
COMPUTERNAME NXBB-PC
COMSPEC C:\Windows\system32\cmd.exe
DOCKER_TOOLBOX_INSTALL_PATH d:\Program Files\Docker Toolbox
FP_NO_HOST_CHECK NO
HOMEDRIVE C:
HOMEPATH \Users\nxbb
LOCALAPPDATA C:\Users\nxbb\AppData\Local
LOGONSERVER \\NXBB-PC
NUMBER_OF_PROCESSORS 4
OS Windows_NT
PATH C:\Python\Python38\Scripts\;C:\Python\Python38\;C:\Python\Python37\Scripts\;C:\Python\Python37\;C:\ProgramData\Oracle\Java\javapath;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Program Files\CMake\bin;C:\Program Files\Git\cmd;C:\Program Files (x86)\Windows Kits\8.1\Windows Performance Toolkit\;C:\Program Files\Microsoft SQL Server\120\Tools\Binn\;D:\Tcl\bin;C:\Python\Python38\Scripts\;C:\Python\Python38\;C:\Python\Python37\Scripts\;C:\Python\Python37\;C:\ProgramData\Oracle\Java\javapath;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Program Files\CMake\bin;C:\Program Files\Git\cmd;C:\Program Files (x86)\Windows Kits\8.1\Windows Performance Toolkit\;C:\Program Files\Microsoft SQL Server\120\Tools\Binn\;d:\Program Files\Docker Toolbox;d:\Program Files\JetBrains\PyCharm 2018.3.5\bin;;C:\Python\Python37;
PATHEXT .COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC;.PY;.PYW
PROCESSOR_ARCHITECTURE AMD64
PROCESSOR_IDENTIFIER Intel64 Family 6 Model 58 Stepping 9, GenuineIntel
PROCESSOR_LEVEL 6
PROCESSOR_REVISION 3a09
PROGRAMDATA C:\ProgramData
PROGRAMFILES C:\Program Files
PROGRAMFILES(X86) C:\Program Files (x86)
PROGRAMW6432 C:\Program Files
PSMODULEPATH C:\Windows\system32\WindowsPowerShell\v1.0\Modules\
PUBLIC C:\Users\Public
PYCHARM d:\Program Files\JetBrains\PyCharm 2018.3.5\bin;
PYCHARM_HOSTED 1
PYCHARM_MATPLOTLIB_PORT 30584
PYTHONIOENCODING UTF-8
PYTHONPATH E:\python\python project;C:\Program Files\JetBrains\PyCharm 2018.3.5\helpers\pycharm_matplotlib_backend
PYTHONUNBUFFERED 1
SESSIONNAME Console
SYSTEMDRIVE C:
SYSTEMROOT C:\Windows
TEMP C:\Users\nxbb\AppData\Local\Temp
TMP C:\Users\nxbb\AppData\Local\Temp
USERDOMAIN nxbb-PC
USERNAME nxbb
USERPROFILE C:\Users\nxbb
VBOX_MSI_INSTALL_PATH C:\Program Files\Oracle\VirtualBox\
VISUALGDB_DIR C:\Program Files (x86)\Sysprogs\VisualGDB\
VS100COMNTOOLS D:\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\Tools\
VS140COMNTOOLS D:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\Tools\
WINDIR C:\Windows
3. 进程
3.1 system()创建进程
import os
#system创建一个进程，并输出其命令信息
print(os.system("dir"))
C:\Python\Python38\python.exe "E:/python/python project/myUrl.py"
Volume in drive E has no label.
Volume Serial Number is DA28-2548
Directory of E:\python\python project
2020/01/15 22:59 <DIR> .
2020/01/15 22:59 <DIR> ..
2020/01/15 22:59 <DIR> .idea
2020/01/15 22:55 15,997 hello world.py
2019/12/31 23:59 84 helloworld.txt
2019/12/29 22:13 398 myModule.py
2020/01/15 22:59 37 myUrl.py
2020/01/15 22:56 <DIR> SQLITE
2020/01/13 22:30 <DIR> venv
2019/12/29 22:24 <DIR> __pycache__
4 File(s) 16,516 bytes
6 Dir(s) 39,953,666,048 bytes free
0
Process finished with exit code 0
3.2 exec()创建进程
import os
#启动一个记事本
notepad = "c:\\windows\\notepad.exe"
os.execl(notepad, "notepad.exe")
3.3 exit()终止进程
import sys
#try部分异常时将执行except捕获
try:
filename = sys.argv[1]
print(filename)
except:
print("Usage:", sys.argv[0], "filename")
sys.exit(1)
C:\Python\Python38\python.exe "E:/python/python project/myUrl.py"
Usage: E:/python/python project/myUrl.py filename
Process finished with exit code 1
3.4 os.abort()终止进程
import os
import sys
#try部分异常时将执行except捕获
try:
filename = sys.argv[1]
print(filename)
except:
print("Usage:", sys.argv[0], "filename")
os.abort(0)
C:\Python\Python38\python.exe "E:/python/python project/myUrl.py"
Traceback (most recent call last):
File "E:/python/python project/myUrl.py", line 6, in <module>
filename = sys.argv[1]
IndexError: list index out of range
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "E:/python/python project/myUrl.py", line 10, in <module>
os.abort(0)
TypeError: abort() takes no arguments (1 given)
Usage: E:/python/python project/myUrl.py filename
Process finished with exit code 1
4. subprocess
4.1subProcess模块管理进程
import subprocess
ping = subprocess.Popen(args="ping -n 4 www.baidu.com", shell=True)
print(ping.pid)
print(ping.returncode)
上面没有加等待子进程结束，导致ping的命令信息在Pycharm控制台上没有看到，现在增加等待子进程结束可以正常显示了
import subprocess
ping = subprocess.Popen(args="ping -n 4 www.baidu.com", shell=True)
#增加子进程等待执行结束
ping.wait()
print(ping.pid)
print(ping.returncode)
C:\Python\Python38\python.exe "E:/python/python project/myUrl.py"
Pinging www.a.shifen.com [163.177.151.110] with 32 bytes of data:
Reply from 163.177.151.110: bytes=32 time=16ms TTL=47
Reply from 163.177.151.110: bytes=32 time=17ms TTL=47
Reply from 163.177.151.110: bytes=32 time=18ms TTL=47
Reply from 163.177.151.110: bytes=32 time=17ms TTL=47
Ping statistics for 163.177.151.110:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 16ms, Maximum = 18ms, Average = 17ms
2860
0
Process finished with exit code 0
由于子进程的调试信息无法输出，可以通过以下方式进行输出到当前控制台
import subprocess
ping = subprocess.Popen(args="ping -n 4 www.baidu.com", shell=True)
#增加子进程等待执行结束
ping.wait()
#读取进程的输出信息
print(ping.stdout.read())
print(ping.pid)
print(ping.returncode)
C:\Python\Python38\python.exe "E:/python/python project/myUrl.py"
Pinging www.a.shifen.com [163.177.151.110] with 32 bytes of data:
Reply from 163.177.151.110: bytes=32 time=17ms TTL=47
Reply from 163.177.151.110: bytes=32 time=17ms TTL=47
Reply from 163.177.151.110: bytes=32 time=22ms TTL=47
Reply from 163.177.151.110: bytes=32 time=23ms TTL=47
Ping statistics for 163.177.151.110:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 17ms, Maximum = 23ms, Average = 19ms
Traceback (most recent call last):
File "E:/python/python project/myUrl.py", line 8, in <module>
print(ping.stdout.read())
AttributeError: 'NoneType' object has no attribute 'read'
Process finished with exit code 1
4.2 subprocess调用外部命令
这条命令与os.sytem是相同的
import subprocess
subprocess.call("dir", shell=True)
C:\Python\Python38\python.exe "E:/python/python project/myUrl.py"
Volume in drive E has no label.
Volume Serial Number is DA28-2548
Directory of E:\python\python project
2020/01/15 23:53 <DIR> .
2020/01/15 23:53 <DIR> ..
2020/01/15 23:53 <DIR> .idea
2020/01/15 22:55 15,997 hello world.py
2019/12/31 23:59 84 helloworld.txt
2019/12/29 22:13 398 myModule.py
2020/01/15 23:53 56 myUrl.py
2020/01/15 22:56 <DIR> SQLITE
2020/01/13 22:30 <DIR> venv
2019/12/29 22:24 <DIR> __pycache__
4 File(s) 16,535 bytes
6 Dir(s) 39,953,141,760 bytes free
Process finished with exit code 0
5. 进程间的信号机制
import subprocess
import signal
def signal_handle(signum, fram):
print("signal handle: signum=%d" % signum)
signal.signal(signal.SIGINT, signal_handle)
ping = subprocess.Popen(args="ping -n 10 www.baidu.com", shell=True)
ping.wait()
print(ping.pid)
print(ping.returncode)
6. 线程
6.1 _thread模块
import _thread
import time
def worker(index, create_time):
#time.sleep(1)
print((time.time()-create_time), index)
print("Thread %d exit..." % (index))
for index in range(5):
time.sleep(1)
_thread.start_new_thread(worker, (index, time.time()))
time.sleep(3)
print("Main thread exit...")
C:\Python\Python38\python.exe "E:/python/python project/myThread.py"
0.0010001659393310547 0
Thread 0 exit...
0.0 1
Thread 1 exit...
0.0010001659393310547 2
Thread 2 exit...
0.0 3
Thread 3 exit...
0.0 4
Thread 4 exit...
Main thread exit...
Process finished with exit code 0
6.2 threading.Thread
import threading
import time
class ThreadSkeleton(threading.Thread):
def __init__(self, index, create_time): #线程构造函数
threading.Thread.__init__(self)
self.index = index
self.create_time = create_time
def run(self):
time.sleep(1)
print((time.time() - self.create_time), "\t", index)
print("Thread %d exit..." % (self.index))
for index in range(5):
thread = ThreadSkeleton(index, time.time())
thread.start()
time.sleep(5)
print("*********************")
C:\Python\Python38\python.exe "E:/python/python project/myThread.py"
1.0000569820404053 4
Thread 0 exit...
1.0000569820404053 41.0000569820404053
Thread 1 exit...
1.0000569820404053 4
Thread 3 exit...
4
Thread 2 exit...
1.0010571479797363 4
Thread 4 exit...
*********************
