def test_state_is_None(self):
"""Tests fileinput.fileno() when fileinput._state is None.
Ensure that it raises RuntimeError with a meaningful error message
and does not modify fileinput._state"""
fileinput._state = None
with self.assertRaises(RuntimeError) as cm:
fileinput.fileno()
self.assertEqual(("no active input()",), cm.exception.args)
self.assertIsNone(fileinput._state)
def test_state_is_not_None(self):
"""Tests fileinput.fileno() when fileinput._state is not None.
Ensure that it invokes fileinput._state.fileno() exactly once,
returns whatever it returns, and does not modify fileinput._state
to point to a different object."""
fileno_retval = object()
instance = MockFileInput()
instance.return_values["fileno"] = fileno_retval
instance.fileno_retval = fileno_retval
fileinput._state = instance
retval = fileinput.fileno()
self.assertExactlyOneInvocation(instance, "fileno")
self.assertIs(retval, fileno_retval)
self.assertIs(fileinput._state, instance)
def test_state_is_not_None(self):
"""Tests fileinput.fileno() when fileinput._state is not None.
Ensure that it invokes fileinput._state.fileno() exactly once,
returns whatever it returns, and does not modify fileinput._state
to point to a different object."""
fileno_retval = object()
instance = MockFileInput()
instance.return_values["fileno"] = fileno_retval
instance.fileno_retval = fileno_retval
fileinput._state = instance
retval = fileinput.fileno()
self.assertExactlyOneInvocation(instance, "fileno")
self.assertIs(retval, fileno_retval)
self.assertIs(fileinput._state, instance)
import fileinput
for line in fileinput.input('example.py'):
print(fileinput.fileno())
#!/usr/bin/python
from __future__ import print_function
import fileinput
for line in fileinput.input():
meta = [
fileinput.filename(),
fileinput.fileno(),
fileinput.filelineno(),
fileinput.isfirstline(),
fileinput.isstdin()
]
print(*meta, end="")
print(line, end="")
def evaluate_line(line_to_evaluate,debug):
# evaluate the line for special exit condition
check_if_exit(line_to_evaluate)
# check if the string is changing directories
test_cd = check_if_change_directory_command(line_to_evaluate)
# initalize variable for piping
shell_piping= check_if_pipes(line_to_evaluate)
#initalize commands array
commands = []
# if there are pipe characters from the check_if_pipes method then set the commands array
# to this array of commands. If not make the commands array an array of length 1 with the
# current line as the command.
if shell_piping:
commands = convert_line_to_array_of_commands(line_to_evaluate)
else:
commands.append(line_to_evaluate)
if debug:
formatted_string = "here is the list of commands: {}".format(commands)
os.write(2,formatted_string.encode())
# iterate through the commands array and execute the commands. For shell re-direction and pipes
# there needs to be file descriptor manipulation and we need to fork, duplicate, and close the processes
# that execute these commands.
command_index = 0
for command in commands:
# if the change directory function was true, skip the command loop and return to my_get_line
if test_cd:
break
# Debugging code
if debug:
os.write(2,("Here is the current command: {}\n".format(command)).encode())
# get the process id of the parent
pid = os.getpid()
# if there is piping call the start_pipe function and set the file descriptors and make them inhertiable
if shell_piping:
file_discriptor_read, file_discriptor_write = start_pipe()
else:
file_discriptor_read = 0
file_discriptor_write = 1
# debugging code
if debug:
os.write(2, ("About to fork (pid: {})\n".format(pid)).encode())
# fork the process
run_commands = os.fork()
if run_commands < 0:
os.write(2, ("fork failed, returning {}\n".format(run_commands)).encode())
sys.exit(1)
# go and have the children attempt to run their commands
elif run_commands == 0: # child
if shell_piping:
os.close(1) # redirect child's stdout
os.set_inheritable(os.dup(file_discriptor_write), True)
if debug:
formatted_string = "Child: My pid== {}. Parent's pid= {}\n".format(os.getpid(), pid).encode()
os.write(2, formatted_string)
# check if there is file redirection
test_redirect = check_if_redirecting(command)
# convert the line that I've read using my_get_line and then converting to an array
# and pass these as arguments to this loop to see if that binary exists in any
# of the below paths
if test_redirect:
command = test_redirect
args = convert_line_to_array(command)
# Get each of the path directories to search for binaries
directories = re.split(":", os.environ['PATH'])
for dir in directories: # try each directory in the path
program_path = "{}/{}".format(dir, args[0]) # append the file trying to be executed to the path
if debug:
os.write(2, ("Child: ...trying to exec {}\n".format(program_path).encode()))
try:
os.execve(program_path, args, os.environ)
except FileNotFoundError: # ...expected
pass # ...fail quietly
for file_descriptor in (file_discriptor_read,file_discriptor_write):
os.close(file_descriptor)
formatted_string = "Whoa whoa whoa! Couldn't find: [{}] as a command! Try a different command \n".format(args[0])
os.write(2, formatted_string.encode())
#sys.exit(1) # terminate with error
else: # parent (forked ok)
childPidCode = os.wait()
if shell_piping:
os.close(0)
os.set_inheritable(os.dup(file_discriptor_read), True)
for file_descriptor in (file_discriptor_write,file_discriptor_read):
os.close(file_descriptor)
for line in fileinput.input():
os.write(1,("FD: %s From child: <%s>" % (fileinput.fileno(),line)).encode())
if debug:
os.write(1, ("Parent: My pid=%d. Child's pid=%d\n" %
(pid, run_commands)).encode())
if childPidCode[1] > 0:
formatted_string = "Program terminated with exit code: {}\n".format(childPidCode[1])
os.write(2, formatted_string.encode())
command_index +=1
#!/usr/bin/env python3 #标准注释，保证.py文件可在unix系统上运行
# -*- coding: utf-8 -*- #标准注释，表示.py文件都用标准UTF-8编码
# 'a test module' # 模块的文档注释，任何模块代码的第一个字符串都被视为模块的文档注释
__author__ = 'zxw' #作者名
import sys
import os # 导入模块
import fileinput
for line in fileinput.input():
meta = [fileinput.filename(),fileinput.fileno(),fileinput.isfirstline()]
print(*meta,end=" ")
print(line,end=" ")
import fileinput
for line in fileinput.input():
meta = ["文件名:" + str(fileinput.filename()),
" 文件描述符:" + str(fileinput.fileno()),
" 行号:" + str(fileinput.filelineno()),
" 首行:" + str(fileinput.isfirstline()),
" 标准输入:" + str(fileinput.isstdin()) + " "]
meta_ljust = [i.ljust(9) for i in meta]
print(*meta_ljust, end="")
print(line, end="")
#-*- coding: UTF-8 -*-
__author__ = 'mcxiaoke'
import os,fileinput
# 内部使用FileInput类实现
# fileinput 是一个从标准输入或者文件按行读入的工具类，默认是文本模式，一般的用法是
for line in fileinput.input(['file_input.py']):
print fileinput.filename() # 文件名
print fileinput.fileno() #文件描述符，int
print fileinput.lineno() #总的行号
print fileinput.filelineno() #当前文件的行号
print fileinput.isstdin() # 是否标准输入
print fileinput.isfirstline() # 是否是文件的第一行
print fileinput.nextfile() # 关闭当前文件，开始读下一个文件
print fileinput.close() # 关闭输入序列
def update_event(self, inp=-1):
self.set_output_val(0, fileinput.fileno())
#!/usr/bin/python
#-*-coding:UTF-8-*-
from __future__ import print_function
import sys
import fileinput
def get_content():
return sys.stdin.readlines()
# print(get_content())
for line in fileinput.input():
meta = [fileinput.filename(), fileinput.fileno(), fileinput.filelineno(), \
fileinput.isfirstline(), fileinput.isstdin()]
print(*meta, end="")
print(line, end="")
