Python中subprocess模块的使用

执行命令：

>>> subprocess.call(["ls", "-l"])
0
>>> subprocess.call("exit 1", shell=True)
1

测试调用系统中cmd命令,显示命令执行的结果:

x=subprocess.check_output(["echo", "Hello World!"],shell=True)

print(x)
"Hello World!"

测试在python中显示文件内容:

y=subprocess.check_output(["type", "app2.cpp"],shell=True)

print(y)
#include <iostream>
using namespace std;
......

查看ipconfig -all命令的输出,并将将输出保存到文件tmp.log中:

handle = open(r'd:\tmp.log','wt')
subprocess.Popen(['ipconfig','-all'], stdout=handle)

查看网络设置ipconfig -all,保存到变量中:

output = subprocess.Popen(['ipconfig','-all'], stdout=subprocess.PIPE,shell=True)
oc=output.communicate()#取出output中的字符串
#communicate() returns a tuple (stdoutdata, stderrdata).
print(oc[0]) #打印网络信息

Windows IP Configuration

Host Name . . . . .

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):

child1 = subprocess.Popen(["dir","/w"], stdout=subprocess.PIPE,shell=True)
child2 = subprocess.Popen(["wc"], stdin=child1.stdout,stdout=subprocess.PIPE,shell=True)
out = child2.communicate()
print(out)
('      9      24     298\n', None)

如果想频繁地和子线程通信,那么不能使用communicate();因为communicate通信一次之后即关闭了管道.这时可以试试下面的方法:

p= subprocess.Popen(["wc"], stdin=subprocess.PIPE,stdout=subprocess.PIPE,shell=True)
p.stdin.write('your command')
p.stdin.flush()
#......do something
try:
#......do something
p.stdout.readline()
#......do something
except:
print('IOError')
#......do something more
p.stdin.write('your other command')
p.stdin.flush()
#......do something more