Python 文件目录操作
File 操作
file.close()
# test.py
file = open("runoob.txt", "wb")
print("file name: ", file.name)
file.close()
[root@master python3_learning]# python3 test.py
file name: runoob.txt
file.flush()
flush() 方法是用来刷新缓冲区的，即将缓冲区中的数据立刻写入文件，同时清空缓冲区，不需要是被动的等待输出缓冲区写入。
一般情况下，文件关闭后会自动刷新缓冲区，但有时你需要在关闭前刷新它，这时就可以使用 flush() 方法。
file.fileno()
fileno() 方法返回一个整型的文件描述符(file descriptor FD 整型)，可用于底层操作系统的 I/O 操作。
# test.py
file = open("runoob.txt", "wb")
print("file name: ", file.name)
fid = file.fileno()
print("file descriptor: ", fid)
file.close()
[root@master python3_learning]# python3 test.py
file name: runoob.txt
file descriptor: 3
file.isatty()
# test.py
file = open("runoob.txt", "wb")
print('is a tty? ：', file.isatty())
file.close()
[root@master python3_learning]# python3 test.py
is a tty? ： False
file.read()
read() 方法用于从文件读取指定的字节数，如果未给定或为负则读取所有。
# runoob.txt
first line
second line
third line# test.py
file = open("runoob.txt", "r+")
print("file name: ", file.name)
line = file.read(10)
print("the string of reading: %s" % (line))
line = file.read()
print("the string of reading: %s" % (line))
file.close()
[root@master python3_learning]# python3 test.py
file name: runoob.txt
the string of reading: first line
the string of reading:
second line
third linefile.readline()
# runoob.txt
first line
second line
third line# test.py
file = open("runoob.txt", "r+")
print("file name: ", file.name)
line = file.readline()
print("the first line of reading: %s" % (line))
line = file.readline(5)
print("the string of reading: %s" % (line))
file.close()
[root@master python3_learning]# python3 test.py
file name: runoob.txt
the first line of reading: first line
the string of reading: secon
file.readlines()
# runoob.txt
first line
second line
third line# test.py
file = open("runoob.txt", "r+")
print("file name: ", file.name)
line = file.readlines()
print("the result of reading: %s" % (line))
file.close()[root@master python3_learning]# python3 test.py
file name: runoob.txt
the result of reading: ['first line\n', 'second line\n', 'third line\n']file.seek()
fileObject.seek(offset[, whence])
-
offset -- 开始的偏移量，也就是代表需要移动偏移的字节数，如果是负数表示从倒数第几位开始。
-
whence：可选，默认值为 0。给 offset 定义一个参数，表示要从哪个位置开始偏移；0 代表从文件开头开始算起，1 代表从当前位置开始算起，2 代表从文件末尾算起。
# test.py
f = open("workfile", "rb+")
f.write(b'0123456789abcdef')
print(f.seek(5))
print(f.read(2))
print(f.seek(-3, 2))
print(f.read(1))[root@master python3_learning]# python3 test.py
5
b'56'
13
b'd'
file.tell()
# runoob.txt
first line
second line
third line# test.py
file = open("runoob.txt", "r+")
print("file name: ", file.name)
pos=file.tell()
print('current position：%d' % (pos))
line = file.readline()
print("the result of reading: %s" % (line))
pos=file.tell()
print('current position：%d' % (pos))
file.close()
[root@master python3_learning]# python3 test.py
file name: runoob.txt
current position：0
the result of reading: first line
current position：11
file.truncate()
# runoob.txt
first line
second line
third line# test.py
file = open("runoob.txt", "r+")
print("file name: ", file.name)
file.truncate(8)
line = file.read()
print('the result of reading：%s' % (line))
file.close()
[root@master python3_learning]# python3 test.py
file name: runoob.txt
the result of reading：first li
file.write()
# runoob.txt
first line
second line
third line# test.py
file = open("runoob.txt", "r+")
print("file name: ", file.name)
# write a new line after the file end
file.seek(0, 2)
line = file.write('hello world')
file.seek(0, 0)
line = file.readlines()
print('the result of reading：%s' % (line))
file.close()
[root@master python3_learning]# python3 test.py
file name: runoob.txt
the result of reading：['first line\n', 'second line\n', 'third line\n', 'hello world']
file.writelines()
# test.py
file = open("runoob.txt", "w")
print("file name: ", file.name)
seq = ['hello\n', 'world\n']
file.writelines(seq)
file.close()
[root@master python3_learning]# python3 test.py
file name: runoob.txt
# runoob.txt
hello
worldOS 操作
os.walk
# test.py
import os
for root, dirs, files in os.walk("/root/workspace/shell_learning", topdown=False):
print(root, dirs, files)
[root@master shell_learning]# python3 test.py
/root/workspace/shell_learning/test1_dir [] ['out.txt']
/root/workspace/shell_learning/test2_dir/test1_dir [] ['out.txt']
/root/workspace/shell_learning/test2_dir ['test1_dir'] []
/root/workspace/shell_learning ['test1_dir', 'test2_dir'] ['passwd.txt', 'user.txt', 'get-docker.sh', 'textfile.txt', 'file1.txt', 'file2.txt', 'test.rb', 'textfile.txt.link', 'textfile2.txt', 'out.txt', 'test.txt', 'file3.txt', 'out.txt.link', 'test.sh']