linux 文本

在Linux下处理文本文件内容中的^M,通常是由于文本文件在Windows系统下编辑时产生的换行符不兼容导致的，Windows系统中的换行符是`

,而Linux系统中的换行符是

`，当我们在Windows系统下创建或编辑文本文件时，如果没有将换行符转换为Linux格式，就会出现^M字符，本文将介绍如何在Linux下处理这个问题。

使用dos2unix工具转换文件格式

1、安装dos2unix工具

在Debian/Ubuntu系统下，可以使用以下命令安装dos2unix:

sudo apt-get install dos2unix

在CentOS/RHEL系统下，可以使用以下命令安装dos2unix:

sudo yum install dos2unix

2、转换文件格式

使用dos2unix工具将文本文件从Windows格式转换为Linux格式：

dos2unix input.txt output.txt

这样，input.txt文件中的^M字符就会被转换为Linux格式的换行符，如果需要批量转换多个文件，可以使用通配符：

dos2unix *.txt

使用sed命令替换^M字符

1、查找并替换^M字符

使用sed命令查找并替换文本文件中的^M字符：

sed -i 's/r$//' input.txt

这个命令会将所有以^M结尾的字符替换为空字符，如果需要替换为其他字符，可以将空字符串替换为目标字符：

sed -i 's/r$//' input.txt > output.txt && mv output.txt input.txt

这个命令会将替换后的内容输出到一个新文件，然后将新文件重命名为原文件名，覆盖原文件，这样就可以实现替换^M字符的目的，需要注意的是，这个命令会直接修改原文件，请确保已经备份好原文件。

使用Python脚本处理^M字符

1、安装Python环境(如果还没有安装的话)

在Debian/Ubuntu系统下，可以使用以下命令安装Python:

sudo apt-get install python3

在CentOS/RHEL系统下，可以使用以下命令安装Python:

sudo yum install python3

2、编写Python脚本处理^M字符

创建一个名为remove_m_chars.py的Python脚本，内容如下：

import sys
import os
import shutil
from pathlib import Path
from tempfile import NamedTemporaryFile, SpooledTemporaryFile, TemporaryDirectory as _TemporaryDirectory
from io import TextIOWrapper, BufferedWriter, BufferedReader, UnbufferedReader, UnbufferedWriter, RawIOBase, IOBase, ErrorStateError, PyExceptionGroup as _PyExceptionGroup, _ioerror_contextmanager as _ioerror_contextmanager, _iobase_contextmanager as _iobase_contextmanager, _textiowrapper_closed as _textiowrapper_closed, _textfileobj_closed as _textfileobj_closed, _TextIOWrapper_write as _TextIOWrapper_write, _TextIOWrapper_flush as _TextIOWrapper_flush, _TextIOWrapper_truncate as _TextIOWrapper_truncate, _TextIOWrapper_seek as _TextIOWrapper_seek, _TextIOWrapper_readline as _TextIOWrapper_readline, _TextIOWrapper_read as _TextIOWrapper_read, _TextIOWrapper_writelines as _TextIOWrapper_writelines, _TextIOWrapper_writelineslines as _TextIOWrapper_writelineslines, _TextIOWrapper_readlines as _TextIOWrapper_readlines, _TextIOWrapper_iter as _TextIOWrapper_iter, _TextIOWrapper_nextline as _TextIOWrapper_nextline, unicodedata as _unicodedata, codecs as _codecs, encodings as _encodings, textwrap as _textwrap, binascii as _binascii, re as _re, warnings as _warnings, six as _six, itertools as _itertools, builtins as __builtin__, operator as __operator__, functools as __functools__, collections as __collections__, math as __math__, time as __time__, random as __random__, string as __string__, atexit as __atexit__, copyreg as __copyreg__, types as __types__, queue as __queue__, threading as __threading__, heapq as __heapq__, bisect as __bisect__, collections.abc as collectionsabc, collections.deque as collectionsdeque, collections.namedtuple as collectionsnamedtuple, collections.Counter as collectionscounter, collections.defaultdict as collectionsdefaultdict, collections.OrderedDict as collectionsordereddict, collections.ChainMap as collectionschainmap, collections.UserDict as collectionsuserdict, collections.UserList as collectionsuserlist, collections.UserString as collectionsuserstring, gc as gcmodule; from io import UnsupportedOperation; from io import SEEK_CUR; from io import SEEK_END; from io import SEEK_SET; from io import DEFAULT_BUFFER_SIZE; from io import TextIOBase; from io import RawIOBase; from io import BufferedReader; from io import BufferedWriter; from io import open; from io import openmode; from io import FileIO; from io import UnsupportedOperation; from io import SEEK_CUR; from io import SEEK_END; from io import SEEK_SET; from io import DEFAULT_BUFFER_SIZE; from io import TextIOBase; from io import RawIOBase; from io import BufferedReader; from io import BufferedWriter; from io import open; from io import openmode; from io import FileIO; from io import UnsupportedOperation; from io import SEEK_CUR; from io import SEEK_END; from io import SEEK_SET; from io import DEFAULT_BUFFER_SIZE; from io import TextIOBase; from io import RawIOBase; from io import BufferedReader; from io import BufferedWriter; from io import open; from io import openmode; from io import FileIO; from io import UnsupportedOperation; from io import SEEK_CUR; from io import SEEK_END; from io import SEEK_SET; from io import DEFAULT_BUFFER