最後更新: 2015-10-12

Sys Class

This module provides access to some variables used or maintained by the interpreter

目錄

• sys.exit()
• version
• sys.argv
• getopt()

import

import sys

sys.exit()

sys.exit()           # 相當於 sys.exit(0)

Exit code:  0

version

print(sys.version)

3.6.8 (default, Oct 25 2023, 15:15:22)
[GCC 8.5.0 20210514 (Red Hat 8.5.0-20)]

print(sys.version_info)

sys.version_info(major=3, minor=6, micro=8, releaselevel='final', serial=0)

sys.argv

The list of command line arguments passed to a Python script. argv[0] is the script name

Code:

sys.argv.py

import sys

print sys.argv
print len(sys.argv)

./sys.argv.py 123 456

['./sys.argv.py', '123', '456']
3

./sys.argv.py -n 123 -m 456

['./sys.argv.py', '-n', '123', '-m', '456']
5

getopt

Helps scripts to parse the command line arguments in sys.argv

option, value = getopt.getopt(args, options[, long_options])

args

The argument list to be parsed

i.e.

# without the leading reference to the running program

sys.argv[1:]

options

The string of option letters that the script wants to recognize

當 options 必須帶 argument 時必須加上 colon ':'

i.e

# -f -t X -m

"ft:m"

long_options

The leading '--' characters should not be included in the option name

short & long options

short options: -fV

long options: --foo=V

Example

>>> import getopt
>>> args = '-a -b -cfoo -d bar a1 a2'.split()

>>> args
['-a', '-b', '-cfoo', '-d', 'bar', 'a1', 'a2']

>>> optlist, args = getopt.getopt(args, 'abc:d:')

>>> optlist
[('-a', ''), ('-b', ''), ('-c', 'foo'), ('-d', 'bar')]

>>> args
['a1', 'a2']