python执行命令行:python中执行shell命令行read结果
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python执行shell命令
1 os.system (只有这个方法是边执行边输出,其他方法是最后一次性输出)
可以返回运行shell命令状态,同时会在终端输出运行结果
例如 ipython中运行如下命令,返回运行状态status
os.system('python -V') os.system('tree')
遇到乱码问题可以采用一次性输出来解决。https://www.cnblogs.com/andy9468/p/8418649.html
或者pycharm的乱码问题:https://www.cnblogs.com/andy9468/p/12766382.html
2 os.popen()
可以返回运行结果
import os r = os.popen('python -V').read() print(type(r)) print(r)
或者
In [20]: output = os.popen('cat /proc/cpuinfo') In [21]: lineLen = [] In [22]: for line in output.readlines(): lineLen.append(len(line)) ....: In [23]: line line lineLen In [23]: lineLen Out[23]: [14, 25, ...
3 commands.getstatusoutput('cat /proc/cpuinfo')
如何同时返回结果和运行状态,commands模块:
import commands (status, output) = commands.getstatusoutput('cat /proc/cpuinfo') In [25]: status Out[25]: 0 In [26]: len(output) Out[26]: 3859
4 subprocess.Popen(["ls","-l"], stdout=subprocess.PIPE)
使用模块subprocess
通常项目中经常使用方法为subporcess.Popen, 我们可以在Popen()建立子进程的时候改变标准输入、标准输出和标准错误,并可以利用subprocess.PIPE将多个子进程的输入和输出连接在一起,构成管道(pipe):
import subprocess child1 = subprocess.Popen("tree",shell=True, stdout=subprocess.PIPE) out = child1.stdout.read() print(out.decode('gbk'))
import subprocess child1 = subprocess.Popen("tree /F".split(),shell=True, stdout=subprocess.PIPE) out = child1.stdout.read() print(out.decode('gbk'))
import subprocess child1 = subprocess.Popen(['tree','/F'].split(),shell=True, stdout=subprocess.PIPE) out = child1.stdout.read() print(out.decode('gbk'))
退出进程
size_str = os.popen('adb shell wm size').read() if not size_str: print('请安装 ADB 及驱动并配置环境变量') sys.exit()
封装好的函数:Python执行shell命令
from subprocess import Popen, PIPE def run_cmd(cmd): # Popen call wrapper.return (code, stdout, stderr) child = Popen(cmd, stdin=PIPE, stdout=PIPE, stderr=PIPE, shell=True) out, err = child.communicate() ret = child.wait() return (ret, out, err) if __name__ == '__main__': r=run_cmd("dir") print(r[0]) print(r[1].decode("gbk")) print(r[2])
python执行系统命令-小结:
# (1)os.system # (2)os.popen # (3)使用模块subprocess的Popen # (4)使用模块commands模块 # (1)os.system import os os.system('start .') # (2)os.popen import os ping_list = os.popen("ping 127.0.0.1").readlines() print(ping_list) # (3)py3使用模块subprocess的Popen import subprocess # child1 = subprocess.Popen("tree".split(), shell=True, stdout=subprocess.PIPE) # child1 = subprocess.Popen("tree /F".split(), shell=True, stdout=subprocess.PIPE) child1 = subprocess.Popen(['tree', '/F'].split(), shell=True, stdout=subprocess.PIPE) out = child1.stdout.read() print(out.decode('gbk')) # (4)py2使用模块commands模块 # commands是python2版本里的,在python3.0以上已经没有commands模块了,使用subprocess代替commands import commands (status, output) = commands.getstatusoutput('cat /proc/cpuinfo') print(status) print(output)