Several ways to pass python and shell variables to each other

Python - > Shell:

1. Environment variables

import os  
var=123 or var='123'
os.environ['var']=str(var)  #environ Must be a string    
os.system('echo $var')  

import os  
var=123 or var='123'
os.environ['var']=str(var)  #environ Must be a string   
os.system('echo $var') 

2. String concatenation

import os  
path='/root/a.txt'
var=[1]  
var='bash'
os.system('echo ' + path)                  # Pay attention to echo After the blank space    
os.system('echo ' + str(var[0]))  
os.system('echo ' + var + ' /root/c.sh') # Pay attention to echo And after /root There is a space before    

import os  
path='/root/a.txt'
var=[1]  
var='bash'
os.system('echo ' + path)                  # Pay attention to echo After the blank space   
os.system('echo ' + str(var[0]))  
os.system('echo ' + var + ' /root/c.sh') # Pay attention to echo And after /root There is a space before    

3. Through the pipe

import os  
var='123'
os.popen('wc -c', 'w').write(var)  

The same code at the page code block index 4

4. Go through the paperwork

output = open('/tmp/mytxt', 'w')  
output.write(S)      # Put the string S Written to the file    
output.writelines(L) # Will list L All line strings are written to the file    
output.close()  

output = open('/tmp/mytxt', 'w')  
output.write(S)      # Put the string S Written to the file   
output.writelines(L) # Will list L All line strings are written to the file   
output.close()  

5. Redirects the standard standby output

buf = open('/root/a.txt', 'w')  
print >> buf, '123n', 'abc'

The same code at the page code block index 8

or

print >> open('/root/a.txt', 'w'), '123n', 'abc' # Write to or generate a file    
print >> open('/root/a.txt', 'a'), '123n', 'abc' # additional   

print >> open('/root/a.txt', 'w'), '123n', 'abc' # Write to or generate a file   
print >> open('/root/a.txt', 'a'), '123n', 'abc' # additional   

Shell - > Python:

1. The pipe

import os  
var=os.popen('echo -n 123').read( )  
print var  

The same code at the page code block index 12

2.

import commands  
var=commands.getoutput('echo abc')       # The output    
var=commands.getstatusoutput('echo abc') # Exit status and output results   

import commands  
var=commands.getoutput('echo abc')       # The output   
var=commands.getstatusoutput('echo abc') # Exit status and output results   

3. The file

input = open('/tmp/mytxt', 'r')  
S = input.read( )      # Read the entire file into a string    
S = input.readline( )  # Read the next line (past the line end mark)    
L = input.readlines( ) # Reads the entire file into a list of line strings   

input = open('/tmp/mytxt', 'r')  
S = input.read( )      # Read the entire file into a string   
S = input.readline( )  # Read the next line (past the line end mark)   
L = input.readlines( ) # Reads the entire file into a list of line strings