Eliminate ^M character using vi(Linux)
Sometimes certain characters(for eg.,^M characters)are placed in a
file during a DOS to UNIX conversion.To modify these files with a lot
of ^M symbol at the end of every line,using the vi editor,use the
following command:
This command will find all occurances and replace them with nothing. Here,the :%s is a basic search and replace command in vi. It tells vi to replace the regular expression between the first and second slashes (^M) with the text between the second and third slashes (nothing in this case). The g at the end directs vi to search and replace globally (all occurrences).
:%s/^M//g(To get the ^M hold the control key, press V then M (Both while holding the control key) and the ^M will appear.)
This command will find all occurances and replace them with nothing. Here,the :%s is a basic search and replace command in vi. It tells vi to replace the regular expression between the first and second slashes (^M) with the text between the second and third slashes (nothing in this case). The g at the end directs vi to search and replace globally (all occurrences).
有一点需要注意的是，如果采用命令vi file_name将无法看到这些非法字符，也无法执行上面的替换操作，必须以binary方式打开: vi file_name -b
