Sys module of python standard library module
The role of the sys module
The sys module is used for interpreter-related operations, and is usually used for passing parameters in scripts
Common usage of sys module
The command line argument list passed by sys.argv to the Python script, the first element being the path of the program itself
Sys.executable returns the absolute path of the python interpreter in the current system
Exit in the middle of sys.exit ([arg]) program. Arg=0 is normal exit.
Sys.platform returns the name of the operating system platform, and Linux is linux2,Windows and win32
Sys.path returns the search path of the module, initializing with the value of the PYTHONPATH environment variable
Sys.version gets the version information of the python interpreter program
Sys.stdout.write (str)
Display and demonstration
Position parameter
Import sys
Print (sys.argv [0])
Print (sys.argv [1])
Print (sys.argv [2])
Print (sys.argv [3])
Print ("hello world")
Execution result
.\ sys module .py # sys.argv [0] script name
A # first parameter
B # second parameter
C # third parameter
Hello world
Exit the program halfway
Import sys
Print (sys.argv [0])
Print (sys.argv [1])
Print (sys.argv [2])
Print (sys.argv [3])
Sys.exit ()
Print ("hello world")
Display of implementation results
.\ sys module .py
A
B
C
PS: the print command after sys is not executed
Get module path
When we use the import import module, we search for the imported module name according to the path of the sys.path
Import sys
For i in sys.path:
Print (I)
After implementation
C:\ python36\ python36.zip
C:\ python36\ DLLs
C:\ python36\ lib
C:\ python36
C:\ python36\ lib\ site-packages
Ps displays the value of the PYTHONPATH environment variable
Get the current system platform
Import sys
Sys.platform
'win32'
Get the path to the Python interpreter
Print (sys.executable)
C:\ python36\ python3.exe
Get the version of the python program
Print (sys.version)
3.6.3 (v3.6.3:2c5fed8, Oct 3 2017, 17:26:49) [MSC v.1900 32 bit (Intel)]
