col

Filter control characters

Supplementary instructions

The col command is a standard input text filter that reads text content from the annotation input device and displays the content to the annotation output device. In many UNIX documentation, there are RLF control characters. When we use the shell special characters > and >> to output the contents of the description file into a plain text file, the control characters will become garbled. The col command can effectively filter out these control characters.

grammar

col(option)

Options

-b: Filter out all control characters, including RLF and HRLF;
-f: Filter out RLF characters, but allow HRLF characters to be rendered;
-x: Use multiple space characters to represent tab characters;
-l <Number of buffer columns>: The default memory buffer has 128 columns, and the user can specify the buffer size by himself.